MacGyver returns to his apartment after a trip to Central America to find evidence on a major drug lord. He notes that he came close to getting killed three times and wonders if he's getting a message. However, when he goes into the bathroom, a bearded man wielding a machete slips into the apartment. When MacGyver emerges, the intruder hides briefly, then ambushes MacGyver and demands the evidence. MacGyver denies having it so the man insists on taking him to the Phoenix Foundation to get it. They arrive... and everyone greets MacGyver with a surprise party for his birthday. The machete man reveals that he's Jack Dalton in disguise. Pete explains that he knew MacGyver wouldn't come if he told him, so they left it up to Jack to get him there.
Pete has brought in several of MacGyver's closest friends, including his grandfather Harry. After Harry goes to get some food, Pete gets the evidence from MacGyver and tells him some of his friends couldn't make it and sent some mementos. MacGyver confronts Jack, who claims it was Pete's idea, but they're interrupted when Penny Parker comes over to kiss MacGyver. MacGyver introduces her and Penny talks about how they met in Bulgaria. As Jack flirts with her, MacGyver goes off to look at some of the items people sent him, and Penny notices that he seems depressed.
MacGyver goes over the various mementos such as the map he recovered from a desert command post. He also remembers how many of them almost got him killed. He goes in to check with Pete, who is going over the evidence with Craig Bannister. When Craig goes out, Pete asks how the mission went and MacGyver admits he got lucky, and he may have pressed his luck as far as it goes. MacGyver tells Pete that he wants to resign. Pete tells him to think about what he's saying and warns that MacGyver would go crazy in a week if he ended up behind a desk. MacGyver figures he'll go back to Minnesota, get married, and have a normal life, and asks Pete to draw up his resignation papers.
Outside, Jack is pretending to be a producer to impress Penny, and talks about how he once saved MacGyver when he was stealing a horse in the Middle East. Penny notices his eye is twitching and Jack claims he has allergies. Meanwhile, MacGyver spots photojournalist Kate Connolly and remembers the time they spent in the jungle. He goes over to talk to her and discovers that she's pregnant. She tells him that he's responsible for it and introduces him to her husband Mike Desmond. He hastily back pedals until Kate explains that she met Mike after MacGyver saved her life and she returned to the states and they've having a child. She wonders how MacGyver keeps bouncing around the world and that she gave it up to have a home and family.
As he goes over his mementos, MacGyver finds a can of brake fluid that Bannister has left him, reminding him of the time they escaped from East Germany. Pete reluctantly gives MacGyver the resignation papers to sign. MacGyver goes in to Pete's office and considers signing the papers. Harry finds him and tells him to follow his gut. MacGyver signs the papers Meanwhile, Jack continues to flirt with Penny, who finally reveals she knows he's been lying all the time. Pete then collects the resignation papers and brings up MacGyver's escape in a coffin. He notes that thanks to MacGyver's efforts, a family was brought together. He offers MacGyver a toast and admits he'll miss sharing his old life with him.
Jack wheels in the birthday cake and everyone sings to MacGyver. They ask MacGyver to give a speech and Jack jumps in, only to get booed down. MacGyver talks about his life and how he shared it with everyone along the way. He admits that the party made him realize that the thing about his life is how they all shared their lives with him and he never would have know them if he didn't live his life the way he did, and thanks them all. As people start eating the cake, he asks Pete for the resignation letter back and then tears it up.
Later, MacGyver finds a flare gun sent by Captain Jim Taylor, the man he rescued in Asia. Pete comes over and MacGyver jokes about taping it back together as Pete glares at him.