MacGyver's new mission takes him to Bulgaria. He meets with his contact, Burak, who plays chess in the park. After they give the proper passwords, Burak gives MacGyver the microfilm on a postcard. MacGyver covers it with a stamp, casually picks it up, and leaves. As he stands in line at the airport, a young American woman notices him and starts talking. She introduces herself as Penny Parker, a dancer. Penny decided to stay in Bulgaria after she fell in love with Stephan. However, Stephan started becoming jealous, insisting she stay with him all the time, and she left him. When she notices Stephan enter the airport terminal with two soldiers, Penny hides a pouch in MacGyver's pocket. She goes over to talk to Stephan, who asks her to give back the jewelry he gave to her as a gift. Penny refuses and Stephan doesn't find the pouch on her. Just then, MacGyver goes through the metal detector, and it goes off. Stephan searches him and finds the jewels. He doesn't believe MacGyver's claim that he never saw the pouch before. MacGyver tries to make a run for it, but is quickly cornered and arrested.
Stephan escorts MacGyver and Penny to a customs office and handcuffs them together. He leaves them alone, taking MacGyver's luggage and passport with him. Penny admits she hid the jewelry on MacGyver because he was an American and the closest person she could find. MacGyver wonders why Stephan is holding them when he recovered all of the jewelry and Penny admits that she kept one ring for herself. MacGyver uses a coat rack to break a hole in the wall to get at the luggage conveyer belt on the other side. Chicken wiring in the plaster keeps them from breaking through, so MacGyver makes a crude lasso out of coat hangers. He fastens one end to a chair and hooks the other end on the conveyer belt. The chair smashes through the wall and they ride the conveyer belt to the terminal and make their escape. Stephan gets word of their escape and gives orders that they should be shot on sight as enemies of the state.
Stephan meets with his uncle, Petrovich, who is also his superior in Intelligence. Petrovich finally gets Stephan to admit that he gave his mother's jewelry to Penny. Petrovich grows angry, and Stephan wonders why since his uncle told him the jewels were paste. Petrovich explains that the jewelry was real and he had stolen them from the government treasury. He also explains that someone duplicated a file containing his Swiss bank account numbers, which show the money he made from selling other treasures. Whoever has the file could expose him to his superiors. Stephan's Swiss bank account numbers were also in the file. Petrovich figures that the underground obtained the files and tells Stephan to do whatever he can to find one of their members. Stephan knows of Burak, and Petrovich tells him to do whatever it takes, including torture, to recover the files.
MacGyver and Penny go to the park to contact Burak. He guides them to a shack so they can discuss the matter privately. MacGyver gets the handcuffs open while Burak explains that the ring Penny has is part of a cache that Petrovich looted from the state. He agrees to hide Penny while MacGyver recovers the microfilm from Stephan's apartment. However, Stephan and his men are in the park and give chase. MacGyver and Penny go one way while Burak goes another. The soldiers capture him while MacGyver and Penny take refuge in the center of a carousel. When Stephan and his men come after them, MacGyver throws the carousel into high gear and tosses a box of brass rings into the gears. The sudden stop knocks out Stephan and his men.
MacGyver goes to a restaurant to hide in plain sight, then waits while Penny draws a plan of Stephan's apartment. He figures that Stephan would keep the stolen postcard close to him, and tells Penny to stay at the restaurant. Penny wonders if he really plans to come back for her and MacGyver promises that he'll get her to safety. She admits that she talks a lot and MacGyver reassures her that he likes her because she speaks her mind.
Stephan and Petrovich interrogate Burak and threaten his family until he talks. Burak gives them Penny's name, and Petrovich mistakenly concludes that she's an American agent. He figures that Penny and MacGyver are working together and will try to get the microfilm back. Petrovich sends his nephew to his apartment and tells him to kill MacGyver on sight.
MacGyver sneaks into Stephan's apartment and recovers the postcard. He prepares to leave when Penny knocks on the door. She had to leave the restaurant because the soldiers started buying her drinks, and had nowhere else to go to. When MacGyver wonders how she got in, Penny admits that she knows the doorman. Stephan comes in, and MacGyver hides and tells Penny to do the same. Instead, she sits on the couch and greets Stephan. While she talks to him, MacGyver mixes up some household chemicals to make a smoke screen, then puts a piece of lard covered with oven cleaner crystals in front of a gas pipe. Once his preparations are complete, MacGyver goes out to talk to Stephan. Stephan warns him that the place is surrounded, draws his gun, and tells MacGyver to hand over the postcard. MacGyver stalls until the kitchen chemicals start giving off smoke. Stephan runs to the kitchen, and MacGyver knocks him out. The lard ignites, setting off the gas, and the police try to deal with the fire. MacGyver and Penny throw on nightclothes and slip out pretending to be Stephan's neighbors. MacGyver prepares to hotwire Stephan's car to make their escape, but Penny reveals she grabbed the keys before they left the apartment.
Stephan works out how much gas the car has and how far MacGyver and Penny could go. He then orders his men to guard all the possible turnoffs and gas stations within the radius. Meanwhile, when their car runs low on gas, Penny suggests they go to Petrovich's house. Stephan used to take her there when they were dating. There's no gas, and Stephan arrives since he figured Penny would remember the house from their time together. Stephan asks for the microfilm but it's clear he's not happy with his uncle's embezzlement. He starts to hesitate but Petrovich arrives and tells him to kill both Americans. Stephan doesn't want to kill Penny, figuring that she's no American agent, but Petrovich notes that it doesn't matter because she can still incriminate him. Stephan asks if his uncle's men are nearby in case they might witness the murders, but Petrovich assures his nephew that his men are far down the road. Stephan turns on his uncle and MacGyver knocks him out. Penny hugs her hero, and they take Petrovich's car. Stephan agrees to show them a route along the back roads that the soldiers don't know about.
Petrovich's men finally come to the house and revive their boss. They all go in pursuit of the fugitives. Once back on the highway, MacGyver has Penny drive them up to an oil tanker. He leaps aboard it and stuffs the water hose into the exhaust pipe. He mixes the fuel with water and the carbon monoxide, then sprays it on the road. The resulting mix is so slippery that Petrovich and his men go off the road.
MacGyver, Penny, and Stephan all make it to the border and cross over into Greece. The border guard demands to see their papers, but fortunately Penny knows him as well. As she hugs her former boyfriend, Stephan and MacGyver can only look on, resigned to the inevitable.