Albert was born of parents with superior intellectual genes. He and dozens of other children of his caliber were collected and raised as components of the Wesker children project by the Umbrella Corporation and given the surname "Wesker". He showed particular promise over the other children, which pleased Umbrella's founder, Ozwell E. Spencer. Spencer saw in Wesker the makings of what his children needed. Obviously not coincidentally, Albert would eventually go into the service of the same company that molded him and become a close employee under the watchful eyes of his 'creator', Spencer, all the while unaware of the pharmaceutical president's true intentions and his origins.
Wesker joined the international pharmaceutical enterprise Umbrella at the age of 17 and began working as one of its researchers. In 1977, Wesker was assigned to the Management Training Facility under Doctor James Marcus. Wesker became friends with, and a rival of fellow trainee William Birkin, becoming colleagues and accomplices for years to come. Both Wesker and Birkin were regarded by Marcus as his best apprentices and the only people he trusted. When the Training Facility was closed down on July 29, 1978, the two were personally transferred to the Arklay Research Facility (underneath the Spencer Estate) to continue their own tyrant virus research (while Marcus continued to work on his own), becoming the facility's chief researchers.
Wesker and Birkin's research of the t-virus lasted over 13 years and three different stages. In 1988, when the research reached its third stage (the creation of the Tyrant Bio-weapon), Wesker and Birkin were then ordered by Spencer to assassinate their former mentor, Marcus and steal all of his research. Shortly after, Birkin's research yielded the discovery of the G-virus in the body of Lisa Trevor, a long time test subject of Wesker and Birkin's while at the Arklay facility. When Spencer approved his project in 1991, Wesker began having doubts about Spencer's intentions and requested a transfer to Umbrella's Intelligence Bureau that same year.
In 1996, Wesker joined the newly-founded S.T.A.R.S. division of the Raccoon Police Department, where he worked as a double agent for Umbrella, giving them information on any police investigations. Two years after the formation of S.T.A.R.S., a series of cannibal homicides were reported near the Arklay region. While the public feared these deaths were the work of a local cult, only Umbrella knew the truth. In an effort to control the public outcry, S.T.A.R.S. Bravo team was dispatched to the region to investigate the situation. Wesker used the time they were gone as an opportunity to gather battle data by pitting the members of S.T.A.R.S. against Umbrella's B.O.W.s.
At the same time, Wesker and Birkin were ordered to reclaim the Umbrella Training Facility. Unfortunately, the resurrected James Marcus destroyed any chance of reclaiming it. Forced to destroy the facility, Wesker realized this to be the perfect opportunity to leave Umbrella to pursue his own personal interests. After destroying the escaped failed experiment: The T-001, Wesker encountered the head of Umbrella's paramilitary organisations: Sergei Vladimir, who was Spencer's trusted colonel. He asked where Wesker was going, and Wesker simply said his next mission. Sergei reminded him that the reclamation of the training facility was his mission.
Wesker pointed out that the T-virus had escaped, infecting a great deal of the area. He told Sergei that his intent was to destroy the facility and dispose of it, as it was of no further use. Sergei reminded Wesker that he was not in charge of Umbrella and could not just do as he pleased without his superiors' consent, unaware of Wesker's intentions to leave Umbrella, anyway. He then unleashed his bodyguard, an Ivan against him in order to punish Wesker for his failure and as a reminder of who was in control. Wesker saw the fight as a chance for some entertainment and battled the B.O.W.
Just as the Ivan was about to attack again, an explosion occured in the training facility, above. Wesker gave a soft smile as the facility's charges detonated, and the blast caught Sergei and his Ivan off guard so they could shield themselves. This gave Wesker enough time to slip away and escape the defunct facility, prompting Sergei to say "I guess he didn't like his lesson." Wesker then prepared to dispatch the S.T.A.R.S. Alpha team to the region.
By the following day, all contact with Bravo team was lost and Wesker's Alpha team was dispatched to the site. Upon arrival, Alpha team was attacked by a loose Cerberus pack and then, abandoned by their pilot, Brad Vickers. fter the loss of member Joseph Frost to the dogs, Wesker and the remaining members of Alpha team sought refuge in the nearby mansion, where Wesker had previously worked. Initially ordering everyone to split up, Wesker disappeared and left the remaining members of Alpha team (Chris Redfield, Jill Valentine, and Barry Burton) to fend for themselves.
Of the nine S.T.A.R.S. operatives who entered the mansion (including Wesker himself), only four members of Alpha team, along with Bravo team's Enrico Marini and Rebecca Chambers, managed to survive against the various creatures and bio-organic weapons that infested the facility. In order to ensure the downfall of the other members, Wesker used extortion in order to convince Barry to do his bidding (luring the others to traps) by threatening his family. When Enrico uncovered evidence that implicated Wesker and Umbrella, Wesker murdered Enrico. However, Chris and Jill learned the truth about Wesker and then proceeded to foil his plot by destroying the T-002 Tyrant, along with the facility itself.
During the ensuing chaos, Wesker injected himself with an experimental virus given to him by his partner, William Birkin. After allowing the Tyrant to "kill" him, the virus reanimated his body after the room became empty. This gave him superhuman strength, agility and regeneration, but at the severe cost of the loss of his humanity. The resulting mutation also gave him gold-red cat-like eyes (but these were not immediately noticeable, due to the sunglasses he always wore). Wesker was revived, while the remaining S.T.A.R.S. operatives were convinced that the Tyrant killed him. After reviving, Wesker realized the S.T.A.R.S. had destroyed the Tyrant and escaped with their lives. He then tried to steal the data from the laboratory and escape.
Wesker found that Sergei had downloaded the data to the Russian base and the Red Queen had locked him from the mainframe system. He swore revenge against the remaining S.T.A.R.S. members, Sergei, and the Red Queen. His plans foiled, Wesker resolved to escape the mansion before the self-destruct timer ended. He was forced into a battle with the remaining B.O.W.s on his way to the exit, and praised his new immense when his enemies were swept away with little effort. Wesker mused that he hoped Chris and Jill would live long enough for the three of them to have their "tear-filled reunion", laughing evilly at the thought of seeing them again. He also had to deal with Lisa Trevor, who first approached Wesker outside an elevator leading to the surface from the lab.
Wesker was not expecting Lisa's arrival, believing that S.T.A.R.S. had disposed of her in Jessica's tomb. He managed to incapacitate the creature, saying "Nobody's perfect, not even you, Lisa." He then went up in the elevator, heading back up to the mansion. However, after he left, Lisa rose up from the ground, still not dead. With what little of her mind was left, Lisa had no other goal but to take revenge on the man who experimented on and deformed her. She pursued Wesker up to the mansion, and approached him again in the main hall. Wesker noted that he needed to pick up his pace, as the 'hour glass' was running low. He resloved to find another route, not wishing to waste time with the stubborn Lisa, who he knew would pursue him tirelessly.
Fending off the remaining B.O.W.s, Wesker had several confrontations with Lisa, who continued to note as stubborn and at one point humorously saying "She must like me." He saw why she had been called immortal after all the weaponry he emptied into her and she still got up. Eventually, Lisa unexpectedly turned away from Wesker and walked away, and it seemed she had given up. However, when returning to the main hall, Wesker again saw her, this time hiding behind columns in a corner. She approached him one final time, and Wesker, tired of her stalking, said he would grant her wish for eternal rest. Using his new abilities, Wesker matched the persistence of Lisa, jumping high into the air to avoid her more damaging attacks.
Wesker shot the chandelier above them loose, and lured Lisa under it. She was crushed when it fell, and as Wesker walked out of the main hall, he said "Be a good girl and stay dead this time." He then quickly sprinted through the forest, trying to put as much distance as possible between himself and the mansion before it exploded. When it finally did, taking Lisa with it, Wesker looked back at the burning rubble triumphantly. The scenario served as a metaphorical representation of Wesker's proclaiming of being reborn "like a phoenix emerging from the flame". He saw a new horizon stretch out before him, and thought of how he had risen beyond the human race and "cheated death itself", leaving nothing to oppose him in his quest for power.
With the combat data and bio-weapon research data he acquired from the the mansion, Wesker was able to secure a high-ranking employment position within one of Umbrella's mysterious rivals: "The Organization".
Still holding the illusion of his death, Wesker avoided showing himself and instead took to being the contact between spies and the Oganization. When Raccoon City suffered a t-virus outbreak, Wesker sent an agent by the name of Ada Wong to retrieve the G-virus sample in the (unknowing) possession of William's only daughter Sherry Birkin, hidden within her pendant. Ada managed to retrieve the sample, much to Wesker and the Organization's pleasure
Wesker and the H.C.F. -a heavily armed assault force- attacked the Umbrella facility on Rockfort Island, intent on retrieving a sample of the T-Veronica virus by one of Umbrella's chief researchers Alexia Ashford. . The t-virus was released in the process when armed conflict with Umbrella's guards took place.
The attack succeeded, especially when the T-virus samples and captive B.O.W's in the laboratory section of the facility broke containment and contaminated the Island. However, Wesker and his men failed to find the missing Alexia. Wesker then went to the Antarctic Research Facility, which had also suffered a T-virus outbreak from infected Rockfort employees fleeing to the facility.
It was here Wesker encountered his former subordinate Chris Redfield (who had arrived seeking his missing sister Claire). Wesker failed to gain a sample of the virus from Alexia, especially when he tried to use his own abilities to force her to surrender one, only to be driven back by Alexia's own abilities. Wesker then left Chris to fight Alexia, and secured a sample of the virus from the retrieved corpse of Steve Burnside. The base started its self-destruct sequence, but Wesker engaged Chris in combat, eager to settle the score. Wesker quickly used his immense strength and speed to gain dominance, with Chris refusing to allow Wesker an easy kill. Wesker was poised to deliver the finishing blow, only for an explosion, caused by the priming self-destruct, to knock a flaming pillar in between the two. Wesker, vowing Chris was lucky and next time they met he couldn't count on luck again, escaped the base as it began to crumble and explode around them. Wesker reached an Organization Submarine and sailed away. While the flaming pillar had badly burned Wesker's face, his burns healed sometime later due to his superhuman regenerative capabilities. It would be five years later following this incident in which Wesker and Chris would meet each other for a confrontation once again.
Four years later, in the year 2002 Wesker was later contacted by the leader of the South American drug cartel "Sacred Snakes", Javier Hidalgo. Apparently, a former researcher of Umbrella supplied Javier with the T-virus in an attempt to save his wife, Hilda Hidalgo, with disastrous results. As his daughter, Manuela Hidalgo, had also contracted the T-virus, he requested Wesker's help. Wesker supplied him with the T-Veronica virus in exchange for a large sum of money as well as a share in his dealings. He also gave him specific instructions to utilize the T-Veronica virus, mirroring the ones made by Alexia Ashford.
One year later, in February of 2003, Wesker infiltrated the Russian Umbrella Facility around the same time that Chris and Jill, his former S.T.A.R.S. subordinates, arrived to destroy T-A.L.O.S.. While they managed to eliminate Umbrella's final B.O.W., Wesker himself managed to kill the mutated Sergei Vladimir. He then took Umbrella data from the Red Queen, before deleting the computers memory, shutting down the facility. Shortly thereafter, finally having strong evidence against Umbrella, he brought his findings to the court. With information from Wesker (who operated under the pretence of being a personal friend of the CEO), Umbrella was found guilty and officially shut-down, its top officials suffering legal troubles and an international manhunt began for Ozwell E. Spencer. With the accumulated Umbrella Archives in hand, Wesker had what he needed to create a new Umbrella of his own. Wesker then took the archives and uploaded them to the system within his operations center, having accessibility to all of Umbrella's history and files at his fingertips. He vowed to one day meet Spencer again and succeed him as the one destined to usher in the new future of the world, which Spencer's vision, whatever it had been, failed to accomplish.
Soon after the raid on the Caucasus Facility, Wesker contacted Tricell, another pharmaceutical corporation, and with the wealth of information and resources collected from Umbrella, allowed Tricell to establish a secret bioweapons division, for which Wesker was greatly compensated. He decided to secretly work with them, as they were another valuable asset, and began further independent activities kept secret from his Organization superiors. A particular interest of Wesker was Excella Gionne, an employee of Tricell and descendant of its founders. Her intellect and ambitious nature, matching Wesker's own, caught his eye. He decided that she would serve as a high-level asset, and with his resources provided, he helped her climb through the ranks of Tricell. Excella found Wesker intriguing as well, to the point of romantic attraction. Due to his callous personality, Wesker did not return this affection, seeing Excella as a mere tool. However, he did not outright let her know this, playing along with her to an extent.
Following the fall of Umbrella, Wesker soon proved to be a problem for his Organization superiors. Wesker had always cherished a desire for power, prominence and domination over others, and, seeing Umbrella as power incarnate, used it to hide behind while he made plans of his own. He established a secret organization of his own, using Umbrella's infrastructure retrieved from the Umbrella Caucasus Research Facility, and began recruiting agents such as Jack Krauser into it. When Umbrella folded, and the sanctuary and protection it provided ruined by the surviving Umbrella leaders' constant power struggles, Wesker decided that bringing his new Umbrella to complete fruition was his most necessary goal. He would need to amass much wealth and resources. In order to achieve this, Wesker planned to go down the list of Umbrella's other top rival corporations, sell them samples of Umbrella's viruses they desired, and finance his personal empire. He would keep this agenda secret from his Organization superiors, though they were suspicious.
Wesker began his plot with Tricell (disguised with the name "S"), who had been interested in acquiring a sample of the newly discovered Las Plagas parasitic organism, preferably an advanced Control Plaga developed by Los Illuminados cult leader, Osmund Saddler. Wesker contacted Tricell and struck the deal. He commissioned Ada Wong, his old partner, to once again aid the field portion of the operation, while Wesker himself remained at his hideout and kept in touch with her via digital video feed. All the while, he contacted her for reports and updates in the objective. Wesker was apparently on a deadline to retrieve the sample, and made it his and Ada's most important goal. He also sent Krauser in to help Ada, though they were at conflict. Krauser thought that Ada would betray Wesker and said that neither of them trusted her, and Ada noted in her report that she wondered if Wesker had sent her to keep an eye on Krauser. Nothing suggests which of the two Wesker trusted more, though he considered them both expendable pawns.
Wesker gave Ada assignments to deal with people in the area, including Luis Sera and Leon S. Kennedy. Luis was a contact of theirs, and he was making attempts from inside the cult to steal the Control Plaga sample. Wesker made it important for Ada to watch over Luis, but he was soon killed by Saddler, and the retrieved sample was lost. Wesker was not concerned, simply saying "There will be another time...", and didn't pity Luis. Wesker also saw Leon as an extra obstacle and ordered Ada to kill him, though she insisted he was of no trouble. She was quite reluctant to carry out Wesker's order, as she had formed a bond with Leon in Raccoon City. When Wesker later asked if she had gotten a chance to kill him, she lied and said the opportunity had not come. Wesker decided to let Leon live for the time being and allowed him to serve as further distraction for Saddler's followers. He later informed Ada of the Illuminados' panic due to Leon's actions, and decided to have Krauser kill Leon instead. Ada saved him, not playing by Wesker's rules.
Ada falsely reported Krauser was dead to Wesker, who found it interesting how easily Leon could avoid death. This implies that Wesker was suspicious of Ada and quite aware that she had let Leon live, and that Krauser was alive as well. He decided to let Leon take care of Saddler himself, and told Ada to eliminate either one still standing when the fight ended. He reminded Ada that he was running the show, and required her to put a halt to whoever could stall their plans, including Leon. Krauser himself was later killed for real by Ada, who said that she didn't want to fill out a large amount of paper work should Krauser return alive. Ada later helped Leon destroy Saddler and stole the sample without killing him, though Wesker may have been aware of this. It was revealed that Ada was not at all loyal to Wesker, but still to the Organization, whom Wesker had gone against. She sent him a false Control Plaga sample on their orders (actually a Modified Subordinate Plaga), and brought them the real sample.
This, however, only stalled Wesker's plans temporarily. Tricell still compensated Wesker greatly for the different sample he provided, as they managed to put it to use. Wesker left the Organization shortly afterwards, apparently no longer needing them. Ever since his faked death, Wesker managed to hide himself in the shadows flawlessly, and it was no trouble for him to avoid his vengeful superiors.
Wesker had built a vast array of wealth and resources, and had obtained a sample of every known parasitic and viral agent. However, Wesker's power hunger did not allow him to be satisfied with material possessions. In conjunction with this, he continued to be flooded with questions regarding Spencer's true motivations regarding B.O.W's. In 2006, he discovered the whereabouts of Spencer, his European castle, and traveled there on the first, stormy night of autumn to find answers. Wesker expected Spencer to be surprised by his arrival, but much to his shock, the old man seemed to actually expect Wesker to arrive. It was then Wesker realized that Spencer had been in control of everything from the start, including Wesker's own actions. Spencer revealed that the development of B.O.W's was only a part of achieving his goal of forcing human evolution through viruses. With the birth of a superior human race, Spencer would make himself a god. Spencer required three things to accomplish his dream: the Progenitor virus as a primary viral base, the Umbrella Corporation for funds, and people who would share his ideals when an advanced race came to be. Much to the surprise of Wesker, Spencer revealed Wesker to be the result of the third necessity.
In a plan called the Wesker Plan, Spencer collected hundreds of children from parents of superior intellect throughout the world. These children were all given the surname Wesker after the project's chief researcher, and Spencer used indoctrination and manipulation to install his values into these children. They were then put in controlled environments all over the world under Umbrella's watchful eye. These unaware children would continue to live their lives and received advanced education with the help of Umbrella. One of these children was eventually sent to Umbrella's training facility. That child was Albert Wesker. Spencer then gave all the Wesker children an experimental virus, Albert's being received through Birkin. However, all of Albert Wesker's "siblings" were killed due to the virus. Albert was the only one who survived. Unfortunately, now that the truth was revealed, the only thing impeding Wesker was an old, dying man. Wesker killed Spencer by thrusting his arm through his chest, claiming the right to be a god was now his. He then released his 'creator' and allowed his body to topple over and bleed onto the floor. He looked down upon the corpse of Umbrella's old leader and pondered how arrogant Spencer had been for believing he, a weak old man, could be a god.
Wesker declared that only one with the true capability of being a god could ever deserve that right. Wesker then stood at the window of Spencer's castle and further pondered this new revelation. Spencer's own arrogance manifested into Wesker himself, who decided to carry out his former master's vision of shaping the world with an new and advanced race of humans. Thus, Wesker decided to modify his original plan to resurrect Umbrella, seeing that a pharmaceutical corporation as his empire was insufficient to provide the godly power he sought. He would therefore instead modify and expand his original plan by combining it with a more advanced procedure of the Wesker Plan, as he believed that by doing so would his Umbrella eventually serve as his new world's leadership and godhood infrastructure. Just then, Wesker's old enemies, Chris Redfield and Jill Valentine, entered Spencer's hiding place. They had been hunting Spencer and Wesker, the last of Umbrella's leadership, under the command of the BSAA, and were given a reliable tip to Spencer's whereabouts. They infiltrated the castle, hoping Spencer would lead them to Wesker, but instead found a dead Spencer with a smiling Wesker. The villain took their sudden arrival as a sign: "The weak would always resist the will of the Chosen." A battle immediately ensued. Using his powers, Wesker overcame the two of them combined, outmatching their gun fire and hand to hand skills.
Tossing aside Jill after she failed to turn a knife on him, Wesker sought his revenge on Chris once and for all. However, before he could deal the finishing blow, Jill sacrificed herself by pushing him out of the window, causing the two of them to fall into the chasm below. The BSAA searched for the bodies for months, but were never successful in recovering them, and the two were marked as deceased. In fact, the two survived and Jill was captured by Wesker. After giving Jill the medical treatment she required, Wesker went back to his alliance with Tricell.
While putting Jill in a cryogenic sleep with the intention of turning her into a weapon against Chris, Wesker continued his activities. Wesker again worked with Tricell, and formed a complete partnership with Excella Gionne, who shared his vision for a new world. Wesker prepared to exact his own variation and perfection of Spencer's plan. He continued to help Excella gain higher positions of power within Tricell, and she soon became the CEO of the entire African division. With this partnership, the old Umbrella Africa Research Center was reopened, along with the source of the Progenitor virus. Wesker used the founder of every single viral agent to create the most powerful virus yet, the Uroboros virus. With Uroboros, he planned to spur the next step in human evolution. Although the virus proved to be too poisonous for humans to be of much use, Wesker found a way to make it less poisonous. In Jill were powerful antibodies that were made from her previous infection with the T-virus. Using these antibodies, Wesker was able to perfect Uroboros to suit his needs. He also commissioned an immense Tricell tanker at a dock built behind the facility. He placed a specialized stealth bomber below the boat's deck, planning to launch it at sea as part of his plan.
Using the newly discovered chemical called P30, Wesker attached a device on Jill's chest that would continuously inject Jill with the chemical. With this, he was able to bend Jill to his will and enhance her abilities. By doing this, not only would Jill continue to assist him and Tricell, but she would also serve as a method of revenge against Chris. At the same time, Wesker began placing the Uroboros virus into missiles with the plan of releasing it by jet into the Earth's atmosphere, causing a global outbreak. While preparations were being made for a large Tricell ocean tanker to take off from the Umbrella facility, Wesker and Gionne waited inside the stronghold, which they added to by digging further into the ground to make the facility bigger over the years. As Progenitor research was continued by Tricell scientists, everything previously owned by Umbrella was branded with the Tricell logo. The pair would also use the newly developed Type 2 Plagas and Type 3 Plagas to create an army of Majini from the natives of Kijuju to serve them, including the Ndipaya Tribe. While Las Plagas had been so successful and had secured Excella's position at Tricell thanks to Wesker, she desired a higher position with more power.
Continuing to show her romantic attraction to Wesker, Excella asked if she had proven herself worthy to be Wesker's partner in ruling the world. Wesker sarcastically said she may have and coldly turned down her romance. While Excella believed Wesker would be her king in the new world and she would be his queen, Wesker had other thoughts in mind. He saw himself as a god who would share his power with no one, though he did not outright express this to Excella and still went along with her romance to an extent. Eventually, the B.S.A.A. would dispatch Chris and his new partner Sheva Alomar to capture and interrogate Ricardo Irving, who had been selling B.O.W.s on the black market and was actually working for Tricell and presumably the one who provided Las Plagas to Wesker and Gionne in the first place. After defeating Irving, Chris and Sheva continued to pursue a mysterious woman who had been helping Irving, unaware it was in fact Jill, disguised in a hooded cloak and bird mask. The brainwashed Jill soon reported to Wesker and Gionne that Chris and Sheva had arrived at the facility. Excella "sensed concern" from Wesker about Chris, but he simply told her he would not accept delay while the plan was nearing its final stages.
Excella left with Jill to deal with Chris and Sheva while Wesker stayed on his own in the facility command room. He pondered all that he had accomplished and remembered back to his encounter with Spencer. Though he had killed his creator, Wesker thanked the dead Spencer for providing him with a greater vision for the future and the means to be the god Spencer could never be. While Excella and Jill went to meet Chris and Sheva, Wesker went to the Monarch Room to wait for them to arrive and prepared for his final battle with Chris, knowing that the agent had much time over the years to train for such an encounter. Gionne introduced the pair to the very virus Tricell had been working on in the form of an advanced creature. While the agents fought off the aggressive monstrosity, Gionne and Jill went back to Wesker and waited with him in the Monarch Room. Eventually, Chris and Sheva would catch up to Excella. After a fight with the cloaked Jill, Wesker came in and described the encounter as "one big family reunion". He told Chris he expected him to be "happier to see us". Chris, confused, had no idea what he meant by "us", and Wesker revealed the hooded woman to be Jill, the one Chris and Sheva had been searching for the whole time.
The mind controlled Jill and the superhuman Wesker fought the pair in a two-on-two battle. Excella left for the dock where the tanker was getting ready to leave, and after seven minutes of his spare time, Wesker recieved a phone call from her. He abandoned the fight to finish his plans, leaving Chris and Sheva to deal with Jill. But Chris and Sheva were able to remove the device from Jill's chest and free her from Wesker's control. Leaving Jill at her insistence, they chased the two onto the carrier ship. Wesker would soon betray Excella, infecting her with Uroboros, which killed her. After Chris and Sheva defeated the monstrosity that resulted, they received a call from Jill. According to Jill, Wesker needed to inject a special serum, PG67A/W (A Progenitor-based solution) into himself in order to keep the virus inside of him stable. If too much was injected, it would weaken him. In a previous encounter with Gionne, Sheva had obtained vials of the serum which Gionne had dropped from an open briefcase. With this new knowledge, Chris and Sheva confronted Wesker in a hanger below the deck which contained Wesker's bomber jet. Chris realized that Wesker intended to release Uroboros into the atmosphere using this jet.
They fought through the last of Wesker's Majini forces and confronted him on a platform as he overlooked the jet, savoring that his plans were all falling into place. Throwing the two onto the ground below the jet, Wesker prepared for the final battle as the hanger rose up to the deck of the ship, almost ready to launch the jet. As he engaged the two, Wesker revealed his plan to rule over the newly created world as a god. Working together, Chris and Sheva managed to insert the serum into Wesker, taking advantage of the darkness by turning off the lights around the platform. Weakened, but not defeated, Wesker fled on board the jet, but Chris and Sheva managed to board it before it took off. In a tense battle, they fought Wesker as the jet continued to fly higher into the sky. Tossing Chris aside, Wesker pulled out a hidden 92F pistol and shot at Sheva while she took cover behind a metal pillar. Chris shot at Wesker as he walked toward him, but Wesker used his concentration and reflexes to dodge Chris' fire and shoot at Sheva at the same time, gloating that his plans would soon create his new world. He then aimed his Samurai Edge at Chris, having saved the handgun after his time in S.T.A.R.S. as a devious way to kill his former comrade.
With serum in hand however, Chris and Sheva were now more evenly matched against Wesker, and he was injected by an enraged Chris, who said that he was "just another one of Umbrella's leftovers". Chris managed to open the jet's underside hatch, causing the jet to lose pressure and crash inside an active volcano. Miraculously, Chris and Sheva survived the crash, but Wesker, who had survived as well, wasn't finished yet. He revealed himself again to the duo when walking out to the front of the crashed bomber's roof, his coat and shirt completely removed. He stated he should have killed Chris years ago, to which his nemesis said that was his mistake and that his plans were over. With a menacing chuckle, Wesker walked forward further while saying "Over?... I'm just getting started!" He then turned to a damaged Uroboros missile and smashed into it with his fist. He then deliberately absorbed his creation, and seemed to have a great deal of control over its infection of him.
Wesker used Uroboros in a last ditch effort to kill his nemesis. The tendrils wrapped around several shards of metal and circuitry before spreading to most of Wesker's upper body, giving him a large, deadly, tentacle like appedange. Endowed by the virus, Wesker attacked Chris and Sheva, all the while exaggerating about natural selection, superior DNA, war and pestilence, and his loathe of the current state of the human race. All of this demonstrated that Wesker's calm, collected, and refined exterior had been completely dissolved, along with the last of his sanity. He made repeated attempts to kill both Chris and Sheva, swinging his large arm in a deadly circular manner and lobbing projectiles forged from his tentacles at both of them while they were separated by the breaking ground of the volcano. After taking much fire from Chris, Wesker's other arm succumbed to the growing infection rate of Uroboros and was also absorbed by the virus. Despite this, he somehow managed to keep the rest of his intact. Eveuntually, the fight came to the last surviving platform at the center of the lava river. With a feral shout of Chris' name, Wesker jumped to the platform and prepared for the final portion of the conflict.
However, despite his incredible powers, Wesker was held off by Chris and Sheva, until the ground gave way from under him, causing Wesker to fall into the lava. While Wesker screamed in pain, a helicopter piloted by Jill and Josh Stone came in to rescue Chris and Sheva. They barely managed to climb the ladder Jill threw to them as the ground under them also gave up and sank into the lava. When they were safely aboard, they looked down upon the sinking Wesker, who became enraged to the extreme and shouted Chris' name one last time. Refusing to acknowledge his own mortality, and obsessed with killing Chris Redfield, he used his tentacle-consumed left arm to grab hold of the helicopter and viciously tugged at it in hopes of taking them with him. However, Chris and Sheva fired a pair of RPG-7 rockets at him as he screamed in anger and pain. The rockets went straight through his head, decapitating him, and the resulting explosion sent out a wave of lava that rocked the copter and consumed Wesker's mutated remains. Albert Wesker, the diabolical villain hell-bent on world domination, was finally gone forever, and Chris Redfield and Jill Valentine were free of his influence once and for all.
In the film continuity, he was the chairman of Umbrella, holding regular meetings from his office in Tokyo via hologram, and heading the Umbrella Commitee. He was constantly at odds with Dr. Isaacs. At the end of the film, Alice told him that she intended to come after him, and she'd be bringing her "friends" (clones) with her. Wesker will be the primary antagonist in Resident Evil: Afterlife.