Former swashbuckling actor Guy Roberts and his wife are driving to Hollywood in Guy's vintage '59 Cadillac, and stop at a motel in Mesa for the night. MacGyver is also there and notices the couple and the vintage car. He's meeting with Tony Sullivan, a Syndicate member that saved MacGyver's life in Afghanistan years ago. Now Tony wants MacGyver to provide him with protection in return for the information he's there to provide to the authorities. Tony arrives in the parking lot but two men, Tom and Phil, arrive and try to capture him. Tony tosses his satchel into the Cadillac and tries to make a run for it. When the criminals corner him, he goes for his gun and they shoot him down, and then drive away past MacGyver.
MacGyver calls Pete to give him a status report, and Pete says there's nothing more he can do now and the Feds will take over. MacGyver notices a drunk putting his bottle on Guy's Cadillac. A fight nearly breaks out and MacGyver manages to defuse the situation. Guy and June thank him and explain they're heading to Hollywood where Guy is starring in a new movie. The couple wishes him well and go back to their rooms.
Tom and Phil report to their boss, Michael Talbot, who is staying at the motel. He isn't happy that they disobeyed his orders and failed to capture Tony. They needed Tony alive so that they could get the satchel. Talbot warns that if they don't get the satchel then they're all in trouble.
That night, Guy goes to put the top up on his Cadillac and discovers the satchel on the floor. He opens it and finds hundreds of $20 bills inside. The next morning, the couple checks out but Guy's credit cards are declined. Much to June's surprise, Guy pays in cash and leaves. MacGyver has already checked out but the electrical system on his rented car has shorted out.
Talbot and his men check out and the clerk gives Talbot some of Guy's cash in change. Talbot notices it and roughs up the clerk until he admits that Guy paid and that the couple is on the way to Hollywood in the Cadillac.
As the Roberts drive to Hollywood, June asks where her husband got the money. Guy lies and says that he received an advance fee from the studio. June admits that she figured Guy made up the entire thing as an excuse to take a trip together, and he wonders if that would have been so bad. They spot MacGyver stuck on the road and offer him a lift to the next town. He gladly accepted.
Talbot and his men find the Cadillac and opens fire, trying to force it over. Guy speeds up and MacGyver tosses the luggage at the pursuing car to delay them. Guy desperately stops him from throwing the satchel, so MacGyver tosses the convertible top's back cover at the car. It entangles the wheels, forcing Talbot and his men to briefly stop and clear it. When they come back, MacGyver unfastens the convertible top itself and has Guy raise it. It goes flying off, slamming into Talbot's windshield and forcing him off the road where a tire blows out.
The Cadillac gets about a mile away before the engine goes out and they're forced to pull over. MacGyver checks the fuel line and discovers that it's cracked. Using Guy's ballpoint pen, MacGyver fixes the leak. He then removes the muffler from the bottom of the car, cools it off with water, and then crimps one end. Next he detaches the steering wheel knob, and finally fills the muffler with gas-soaked seat padding. Talbot and his men finish fixing their car and come after them again. Guy drives away and MacGyver uses the muffler as a makeshift cannon to fire the knob at Talbot's car, blowing open the radiator and forcing them off the road again.
The Cadillac finally gives out and they're forced to pull over again. Guy reveals the satchel with the money and June is angry that she liked to him about the job. He claims he did it to make her happy but she doesn't believe him. MacGyver warns that Talbot won't let them go even if they return the money. They spot a deserted town nearby and push the car in neutral down hill to the place. Talbot, Tom, and Phil are following on foot and spot the Cadillac's oil leak, and figure they're close.
In town, MacGyver hides the Cadillac and MacGyver realizes the money is counterfeit. He then removes the car horn and battery from the Cadillac and wires it to the door of a building. As he works, Guy talks about June but MacGyver thinks he's talking about the Cadillac. He finally realizes what Guy is talking about, makes a flower out of a newspaper, and tells Guy to apologize.
Talbot and the others enter the town and split up. MacGyver lures Phil to the Cadillac and then knocks him out with the car hood. Meanwhile, Guy goes to see June, who is hiding in the town jail, and apologizes for what he's put her through. He says he isn't worth it but June insists she loves him and is staying with him. Talbot finds them and herds them outside at gunpoint.
MacGyver runs for the building with the car horn, drawing Tom's attention. When Tom goes inside, he sets off the car horn and MacGyver knocks him out while the man is deafened. Outside, Talbot takes Guy and June to the Cadillac and tells them to give him the counterfeit money. Guy rips off the radio antenna and engages in a fencing duel with Talbot, disarming him. He manages to hold off the crook long enough for MacGyver to knock Talbot unconscious with a well-thrown hubcap.
Talbot and his men go to jail and the counterfeiting ring is busted up. Later, MacGyver collects his mission payment in a favor: the Foundation pays for a body shop to restore the Cadillac to vintage condition. Guy notices one small scratch, but MacGyver quickly blows off the string that looks like a scratch.