Michael Simmons meets with some East German buyers and collects three-quarters of a million for a top-secret navigation system. He tells the buyers that it's ready for them to pick up, and then leaves with his money. His partner, Linda, picks him up, and Simmons tells her that he's successfully scammed the buyers and sold them phony crates. He tells Linda to buy tickets to Rio, then pick him up the next day.
MacGyver is scrimmaging with a pro hockey team and ends up in the penalty box. Pete stops by and MacGyver insists that he promised there wouldn't be any assignments for at least a week. Pete notes that the Foundation is handling an investigation into a security leak at Vectrocon Systems. MacGyver knows all about it and the man responsible, Simmons. They want to find Simmons and seal the leak. MacGyver agrees to take the job, and Pete explains Simmons is heavily invested in a bar downtown.
Mob boss Charles Banning is with his granddaughter at the park when Jimmy Kendall approaches him. Banning's bodyguards try to stop him but Jimmy disposes of them and then Banning warmly embraces him. Banning talks about how he's been in prison for ten years, but Banning promises he has a job for him. Simmons conned Banning out of his money and Banning wants Jimmy to dispose of him. Jimmy warns that it's been ten years and he doesn't have the heart or the knees for it. Banning insists that he's "The Eraser" and can handle any assignment. Jimmy agrees to take on one more job for old time's sake.
At Simmons' bar, MacGyver stops by and helps the bartender repair her soda sprayer. He fixes it with a martini skewer as Jimmy comes in and takes a seat at the bar. They chat and Jimmy complains about his arthritis. MacGyver asks after Simmons and the bartender admits he might be at a nearby car lot. Jimmy follows MacGyver there and watches as he comes up with nothing. MacGyver notices him and catches up to him, and Jimmy claims that Simmons is his son and they were supposed to meet, but Simmons disappeared. Jimmy lies out a convincing story about having never had a chance to watch his son grow up. MacGyver agrees to call him at his hotel once he finds Simmons.
That night, MacGyver goes to Vectrocon to try to get a lead on Simmons. Pete doesn't want to tip off anyone at the company in case there's another mole, so MacGyver sneaks in via the elevator shaft. He bypasses the electrical lock and gets into Simmons' office. He finds a photo and address of Linda, and then sneaks out. However, as soon as he gets outside two men attack him. MacGyver fights back and makes a run for it, but one of them tackles him. A third man arrives but Jimmy steps out and knocks him out, then clutches at his bad leg. Jimmy admits he's been trailing MacGyver to make sure he didn't get hurt. MacGyver goes back to his place with Jimmy, who talks about how he played with the '47 Braves for two whole weeks. He ended up driving the team bus. MacGyver admits he found Simmons' girlfriend Linda, and Jimmy thanks him for putting him up. The two men bond over table hockey and Jimmy figures that MacGyver dreamed of making it in the pros too.
MacGyver follows Linda while Banning's men, the ones who ambushed MacGyver, go to see Jimmy at his hotel. They play poker and Jimmy explains that he's using them to make his story look convincing to MacGyver, and they're not going to eliminate MacGyver because it isn't part of the contract. He's happy to let MacGyver do the legwork, despite thug Ralph's objections.
MacGyver watches as Linda goes up to a cheap brownstone, then gets into her car and rigs the car phone into the car system. He then calls Jimmy and tells him he has found Simmons. Jimmy prepares to leave but Ralph insist on driving on Banning's orders. At the apartment, MacGyver waits until Simmons and Linda are in the car, then calls them and pretends to be ordering a pizza. When Simmons hangs up the car phone, the car doors lock and the engine shuts down. MacGyver walks over and tells them to pick up the phone, freeing up the security system. MacGyver hauls Simmons out and tells Linda to leave, then has Simmons wait until his "father" arrives. Simmons explains that his father is dead. Jimmy and Ralph arrive and MacGyver spots him coming with a gun. They run for it and Jimmy and Ralph give chase. MacGyver ducks into a building and takes refuge in the basement, but they find themselves trapped with no way to bar the door. MacGyver creates a makeshift cannon out of two pipes and a tank of flammable gas. They burst through the door and barricade it before Ralph can get through.
Simmons and MacGyver head for the exit but Jimmy intercepts them. Ralph listens as Jimmy tells MacGyver to get out of the way. MacGyver admits he was wrong but refuses to get out of the way even for scum like Simmons. He reminds Jimmy of how he wanted to just relax and walk away, but Jimmy says it's a contract. MacGyver refuses to move and Jimmy finally tells him to take Simmons away. Ralph hears the entire thing and goes to report to Banning. Simmons tries to run and when MacGyver stops him, Jimmy slips away.
Ralph tells Banning what happened and offers to dispose of Simmons. Banning tells him to take out Jimmy first and then Simmons.
Pete goes to see MacGyver at his apartment and tell him they captured the East Germans. MacGyver is checking the computers and learns that Banning has a contract out on him, and was connected to Simmons. MacGyver figures there's only one place that Jimmy would go, and checks out the local ballfields. He finds Jimmy watching a game, and figures that Banning will figure out where he is as well. Jimmy figures there's no point in running and at least he can go out in style. MacGyver suggests he take on training baseball players and putting his experience to use, rather than just give up. Jimmy starts to see his point, but Ralph and two Banning goons arrive.
MacGyver and Jimmy make a run for it to a nearby balloon warehouse. They slip in and Jimmy warns that even if they escape this time, Banning will keep sending people to kill him. MacGyver looks at the balloons and gets an idea. He takes a roll of mylar and stretches it in a sheet parallel to the floor, then sets up a mirror. In the alley below, Ralph sees Jimmy's reflection and shoots it. Thinking Jimmy is dead, they run upstairs and see him covered in (fake) blood. MacGyver fakes a police siren by blowing on a piece of foil with a comb and the men leave before they can check Jimmy's "corpse."
Ralph reports to Banning that Jimmy is dead. Banning isn't thrilled with what he had to do, and sends flowers to Jimmy's funeral. Pete and MacGyver watch the fake funeral, and Pete assures MacGyver that Jimmy has a new name and personal history, and has been relocated to Florida. MacGyver admits he's found Jimmy a job.
In Florida, Jimmy is helping manage a team and boasts of how for two weeks, his team couldn't go anywhere without him.