Plot

As MacGyver works quickly to rescue survivors from a collapsed building in Germany, he discovers a new safety threat - an undetonated bomb from World War II hidden beneath the rubble.

The Phoenix team works to remove an undetonated World War II bomb from a building in Germany, and race against time to get it out to save the trapped workers. Russ wonders what Boze does at Phoenix, and Desi refuses to abandon a trapped woman even when Mac and Riley fail to defuse the bomb.—Gislef

Alerted that a building is collapsing after an atypical explosion from below in Karlshure (Germany), Mac discovers the cause was a defective time-release allied bomb from World War II. Mac finds a similar bomb that hasn't been detonated yet, so he and Riley try to extract it against the clock without setting it off, despite setbacks. Desi disregards her own safety, determined to save local Helen Beck in the rubble. Russ is concerned about Bozer's role (and his cyber-assistant's) on the team, and vice-versa, so they wager to prove their own value to Phoenix. Mac gets Riley to confide she is dating someone for months, he also hints at his feelings for Riley. Later Russell finds out from initialized evidence that the mysterious organization planning global dismay was established in the 1940s under the name "CODEX."—KGF Vissers

October 1994

A scientist, Dr. Zachary Tutelman, for U.S. military officer how he and his colleagues have used acetone to create a one-hour delay on a fuse. He says that they've got the failure rate down to 10%, and the general in charge says that they'll start implementing manufacture of the new bomb immediately. Once they leave, Tutelman tells his colleague that he didn't become a scientist to come up with better ways to kill people.

Later, the Air Force drops bombs on Kasrlsruhe, Germany. One of the bombs lands in the city but doesn't detonate.

Now

Mac, along with Riley, demonstrates egg drops from a ladder for Cub Scouts. He shows the Scouts a cushioned container to protect the next egg that he drops. Mac gives the Scouts a week to build a similar container to earn their science merit badge. The Scouts are bored, and one of them finally asks why they have to learn the science when he wants to do archery. Mac says that science helps them solve problems, and he uses it in his jobs. One of the Scouts says that the job sounds boring. Aubrey calls Riley to ask when she'll be home, and says that he's making dinner and needs to time the sauce. Riley says that she'll call when she's on the way home. Once Riley hangs up, Matty calls Mac and Riley in. Riley tells Mac that her father called. The pair arrive at Phoenix where the others are waiting. Matty notices Mac wearing his Scout uniform, and explains that three hours ago there was a building in Karlsbuhe. They don't know what caused the blast, but CCTV of the suggesting area suggests it occurred within or below the building's foundation. Mac figures that indicates it wasn't a ruptured gas line or an electrical malfunction. Dozens of construction workers were trapped inside when the building collapsed, so it's a rescue ops with engineering challenges. Russ tells them that he'll be staying back with Matty to coordinate, while Desi has experience with search and rescue so she'll be going with them.

The team arrives in Karlsruhe where crowds have gathered outside the building. The local military officer thanks them for coming but wonders how they can help, and Mac asks him in German how many workers still trapped. The police officer in charge points out the stairwell that collapsed that leads to the workers, but warns that the building is still settling and therefore dangerous. Riley notices the families of the worker in the crowd and figure they can't wait.

Mac goes to work with the rescue team, using a makeshift lever to move the concrete blocking the stairwell. Once they go in, Riley uses the workers' radio signal strength to approximate their locations. As they go, Desi says that she was part of a military group assigned to find survivors after the earthquake in Iraq in 2017. A man yells for help, and the team finds him and call in the medics. The building comes down around them, but no one is harmed. Matty tells everyone to split up and keep moving.

Russ finds Boze in the lab and says that there's nothing Boze can do. He asks what the function of the lab is, why it's so expensive, and what Sparky is. Russ questions the cost, and wants to know what Boze does at Phoenix. Boze insists that he's saved the world hundreds of time, and Russ notes that it's been half a dozen assists at best. When Boze challenges Russ to prove his worth, Russ tells him that he's doing the same and the two of them glare at each other before Russ says that it should be fun.

Mac checks the site of the explosion and reports the others that the blast came from below the building's foundation. He finds curved and oxidized shrapnel and an American serial number on one piece. Mac realizes what caused the explosion: an unexploded American bomb. He finds a second unexploded bomb and warns that it could go off at any moment.

Russ and Boze join Matty, who confirms that the bombs were dropped on one of Hitler's railyards. There are ten workers unaccounted for, and will it take them days to find it. Mac and Riley have to neutralize the bomb while Desi continues searching for the workers. Desi asks them jokingly not to let them blow up and leaves. Mac doesn't know how to disarm mid-century relics.

Russ and Boze go to a World War II museum and Boze tells Mac that he thinks out of the box. The curator, Jenna Bonham, comes in, and Russ says that she's there for a bomb. He has authorization from the Department of Defense, but not enough time to get Jenna's approval. Russ asks Jenna to open the bomb display case, and Hela objects about the lack of protocol. He analyzes her and says that she are constructionist who has had trouble with her superiors, and assures Jenna that he believes in her. Jenna is touched and Russ says that if she hands over the keys he'll get her promoted. Boze watches as Jenna hangs over the keys, and the Phoenix techs remove the bomb.

Desi and the German rescue team get another worker out, and Desi reports to Matty that they have seven more workers to go. The project manager, Helen Beck, calls over the radio, saying that she's trapped and can't move, and asks Desi to tell her family that she's okay. Desi confirms that Helen isn't on Riley's map and tells Matty, then tells Helen that she's going to find her and asks her to keep talking. As Desi looks for Helen, she has her tell her about her family.

Russ puts the bomb through teardown and calls To Mac. Boze tries to take some credit, and Russ says that the fuse inside the bomb was designed to create a one-hour delay. The glass containing the acetone didn't always shatter, meaning it didn't set off the bomb. Boze has found an American pamphlet explaining how the bomb can be defused, and Russ takes credit for translating it. The instructions say that a simple tool can be used to remove the fuse, and Boze sends photos of it to Mac.

Mac figures that they to lift the bomb out of the dirt, and digs a hole beneath the bomb so they can put a cable around it. He asks Riley about her father since she claimed he called, and Mac figures that Riley is hiding a secret. Mac speculates that it's a man, and Riley says that she's been living with Aubrey for six months. He wonders why she would like about it, and Riley points out that Mac hasn't rushed to tell her why he and Desi broke up. Mac drops the matter and uses concrete rubble as weight to lift the bomb out of the dirt.

Once Mac and Riley stop lifting, they realize that the bomb hatch has rusted over. Mac suggests that they remove the bomb from the building, and Riley says that they have to take it out the way they came in. They put the bomb on an EMT gurney, and Matty tells them that the Germans have set up a crane outside. However, they can only attach the crane to a sixth-story window, so Mac and Rile have to move the bomb up six flights of stairs. Mac warns that there are too many variables to calculate if the fuse would go off. Boze and Russ have attached motion sensors to their bomb to give advice to Mac and Riley.

Desi searches for Helen, who asks her how many times she finds herself in situations like it. The younger woman describes how she was in a collapsed building during the Iraq earthquake, and kept searching for the survivor as she tapped on a pipe. Desi tells Helen that she found the survivor.

Boze keeps dropping the bomb, setting off the motion sensors. Russ insists that there's always a solution, and Boze remembers when he was a delivery man using a portable lift device. He tells Russ that he knows what Mac needs to build. Mac makes a powered stairclimber, and he and Riley take the bomb up the stairs. As they go, Mac says that Riley used to talk about everything, and they agree that things have changed since then. Riley tells Mac Aubrey's name and talks about how she hasn't told him about Phoenix. She figures that if she told the team, her relationship with Aubrey would be over. Mac explains that he and Desi realized they weren't suited for each other, and they were just clinging onto something familiar. Living their normal lives just meant they both got on each other's nerves, and Riley wonders if the job will keep them from having normal relationships.

The building shakes and Riley loses her grip. The wheel comes off the stairclimber and the bomb falls down the stairs. Mac jumps down and pulls Riley out of the way just as the bomb hits a wall. Matty calls to ask their status.

Desi loses contact with Helen and goes to find her. Meanwhile, Mac and Riley hear the bomb hissing. Mac puts his ear to the surface and realizes that the acetone capsule broke and the bomb is going to go off. The crane arrives and Desi continues her search for Helen. Mac and Riley get to the sixth floor and Mac figures that they have 40 minutes until the bomb explodes.

As she continues searching, Desi hears metal banging and realizes Helen remembered her story about banging on a pipe and is emulating it.

Russ tells Mac and Riley that they don't have enough time to get the bomb out of the city, but they can submerge it in the Rhine to contain the blast. Mac and Riley come to a 10' wide section of missing floor, and Matty tells Desi to make her way out. Desi refuses to abandon Helen, who is banging on a metal surface with her walkie talkie. The agent finds Helen and manages to get to her through a regular-bursting flame. Helen's leg is trapped beneath a girder.

Mac uses two boards to push the bomb across the hole. They make it, and Matty tells Desi that "they" are on. It's Helen's son Robert.

Riley and Mac get to the edge of the sixth floor, and Mac tells Riley that when they're on a mission, and he's about to do something stupid, he imagines it going wrong and dying. But every time he just regrets that he's alone. One of the crane's hydraulic is punctured by rubble and none of the remaining four workers can be moved in time. Desi refuses to leave the pinned Helen, even though she knows the building will come down.

When Desi tells Mac that she won't leave, Riley spots a truck on the street and says that they need to get the bomb to the ground. She reminds Mac of the egg drop experiment, and Mac tells the team that they're going to drop the bomb. Matty points out that the fall could prematurely detonate the bomb, but Mac figures that after the bomb didn't detonate from 80,000' the first time, 60' more won't set it off.

Boze and Russ rig a containment unit based on Mac's design, and Russ warns Mac that in 43 times it's "destroyed" Phoenix 43% of the time. Mac refuses to flee, and figures that trying to improve the design doesn't outweigh the risks of dropping the bomb. Riley and Mac push the contained bomb out the window, and it doesn't explode. The rescue workers move it onto the truck, and Desi and Helen hug in relief.

Mac and Riley hug, and Riley tells Mac that he's never alone. He says that she isn't as well, and they hold hands briefly.

That night, Riley returns home late and finds Aubrey dinner sitting on the table, reheated. She sits with him but says nothing.

Russ visits Boze and tells him that the team is back home and Helen is with her family. He says that Boze did well, and says that he's figured that Boze is jack-of-all-trades and a master of more than one would imagine. Russ shakes hands with Boze and apologizes for putting Sparky on eBay. Later, Russ tells Mac that he found a photo of Tutelman. A man in a suit, in the photo, is holding a clipboard with a symbol of the organization, and Russ says that he's done more digging and he has discovered what they call themselves.

1944

Tutelman listens to a radio broadcast of D-Day. The man in the suit comes in and tells Tutelman that there are others innovators who think the same as him about the goodness of the war and whether it will destroy the world. The mystery man tells Tutelman that there's a way for him to continue his work and find peace, and just needs to give Tutelman a different perspective. He hands Tutelman a card with the group's symbol and leaves.