At a hidden underground laboratory a series of scientists are looking for the way to travel to a parallel universe. The high-tech building is controlled by a computer whose voice the audience can hear in voice-over. Three scientists are traveling through a kind of machine. There are problems with the images from this other planet. When things go wrong, Dr Julie Casserly (Tara Buckman) and Dr Lisa Myers (Rachel Hayward) know that the team of scientists will only have 8 hours of oxygen to breath with them. There is an argument with Secretary Kenmore (Bob Wild) about what to do next. Other doctors oppose the decision, but finally a rescue team will be sent to the same alternative reality. One of the doctors who oppose the move is Dr Alex Summerfield, (Paul Koslo) who says that things must be left alone and the project closed. The idea of sending a rescue team is upheld, but everybody feels that Dr Ronald "Ron" Shepherd (Jan-Michael Vincent) must be consulted. He blew up his laboratory while he was carrying the same research, and has never wanted to explain why or what happened.
Meanwhile, Zunoski (Rolf Reynolds) and Mancini (Nic Amoroso) are given injections before traveling to that alternative. They try to flirt with Lisa; although she doesn't seem to fall for it she doesn't reject it either. Shepherd visits the new facilities and he coments to Julie that no expense was avoided. Alex is rude to Shepherd, although he has more than a handful with the failures in the Nexus - the computer is failing again. Julie Casserly tells Alex off, as they all should work as a team, but Alex thinks that Ron is a maniac who's going to destroy the project. Alex tries to push Ron out of the building now that the secretary is not there.
Only a person returns from the alternative reality. It's Marshall (Tracy Westerholm). She has fainted, but she is alive. Alex reviews the few images - it's a kind of white sphere, or a weird igloo. The scientists comment that nothing is wrong, but suddenly one of them asks what something was, and then we hear some screaming. Ron reminds everybody that he recommended for the research to be cancelled. Alex is reminded that Ron was there and survived. Julie reminds him that she has put her ass on the line for him.
Meanwhile, Alex has left the meeting room storming off dramatically. He visits Marshall, who wakes up. He asks her whether she can remember what happened - at first, she smiles in silence, but then she tries to strangle Alex and then screams in pain. Alex insists and inquires about Dawson (Michael Metcalfe) and Hoffman (Thom Schioler). Lisa tells him to leave Marshall alone, because if she dies Alex will never ever get any answers.
Alex and Ron are checking Marshall's suit - there's a lot of condensation. Shepherd tries to give Marshall an injection, but Alex prevents it and kicks him. Lisa is witness to the attempt against Marshall's life.
Finally, the rescue mission is ready. McShane (Jano Frandsen), Baines (Nicholas Lea) and Jedburd (W.F. Wadden). Alex thinks that it's jealousy on part of Ron, as he is not the only one who survived the trip now, and he is overjoyed as this is his opportunity of getting rid of Julie.
An alien is born from Marshall - her physical data interferes with the mission computer. The alien explodes from the inside. The alien jumps and runs away through a ventilation shaft. The computer decrees containment. Lisa was going to help Marshall, who is dead now, and now she is in a corridor in the dark. Lisa Myers phones Alex from Shepherd's office. Alex is going to pick her up, but she is terrified because the lightbulb of the desk lamp is off. CCTV shows empty corridors.
Julie and Ron are looking for what has contaminated the area. The rescue team is doing nothing, just picking on one another.
The alien starts rampaging and kills Ford (Gerry Nairn); Marshall's body is also dried out and weirdly looking as burnt. The alien gets Lisa, who's about to have sex with one of the young cocky soldiers from the rescue team. He at least succeeds in ringing the alarm, so that his friends appear and try to shoot the alien, who jumps to the roof again and leaves.
Finally, Ron admits to Julie that he destroyed the Nexus so that nobody else could go. Julie admits she wouldn't have believed Ron without proof. Meanwhile, Alex has an erotic dream with Marshall. He wakes up startled by the realism of the dream. He is constantly popping pills into his mouth and swallowing without even water.
There is a meeting in which the young "warriors" ask Ron about the thing. He says that Dawson and Hoffman are dead, and that a kind of lifeform has entered our planet. It looks like all the floors are underground and are linked by a series of shafts, which will make the lifeform's movement very easy. One of the rescue team suggests that it'd be better for everybody to leave the building. Another suggestion is to wait for reinforcements and stay put until they arrive, but Alex hasn't called for reinforcements, as he thinks that they should clean up their own dirty laundry. In fact, there is no line on the phone, and the computer voice announces that it's locking down everybody to avoid the spread of the contamination. The soldiers get weapons, but they panic while all doors are closing down, locking them in forever.
The aliens appears from inside an air shaft and kills one of the soldiers without the rest of them shooting a single shot or reacting. It's Ron who looks down. The sounds of the alien - sounding like an animal - scare everybody, while every lightbulb is getting broken. Ron gets attacked, and the huge alien jumps in front of Julie, who hides away and then shoots the alien. The monster looks like a mixture from an alien from the film Alien and a dinosaur. It stumps heavily around.
Alex is at control room. Gas is leaking, but he doesn't want to open the door anyway. Another assistant tells them that they can open the door from the inside manually. Julie et al. enter the shaft and walk around looking for a way out. Mancini is killed by the alien - they try to throw a grenade at him, but it doesn't work.
Shepherd thinks that the alien is collecting information. Alex had got scratches in his neck when Marshall attacked him, and now he's feeling worse and worse. He has some horrid ulcers in his body. He tries to commit suicide with a gun in his mouth, but breaks a mirror instead.
The survivors want to contact server service, but it'll be difficult as they have to override the computer's lockdown. They climb the lift shaft to do just that.
Alex threatens Julie with his gun. He is becoming more mad and more corrupted by the alien - a smaller alien grows out of him. The bigger one also appears and Shepherd shoots it.
Finally, Ron puts Alex in the machine to send him to that alien world. The alien is bursting out of Alex; the system malfunctions but sees goodbye to Alex anyway.
Julie and Ron decide to tell the truth, but they know that nobody is going to believe them. Lisa appears, naked, and it speaks with the voice of the alien.