Saturday night sees Fred heading over to Donna's for a date that he didn't tell her about before hand. Once he arrives, he discovers Donna already has a date with a man who's won the decathlon every year in the Senior Olympics. Wanting to outdo him, Fred decides to compete in the Olympics this year and beat his romantic competition.
An alien spacecraft crashlands on the Moon, its passengers refugees from a dying world. As their destination is Earth, they generously offer to take one person with them when they depart. The scheming Commissioner Simmonds takes steps to ensure that he is the lucky individual chosen, even if it means destroying Alpha.
Lieutenant Stone is placed in the awkward position of investigating a burglary with Irene Martin, a lady cop -- who is also his girlfriend who he's just proposed to. She resents his intrusion into 'her' case and their relationship unravels.
A glimpse at Detective Fish's home life ensues when the detective decides to go on restricted duty. Steve Landesberg bows as Arthur Dietrich; Doris Belack fills in for Florence Stanley as Bernice Fish.
Vera Walton has left her husband Wade and moves into the Walton home. Wade has been abusive and is running moonshine. John gives Wade a job at the mill to help the young couple get on their feet and get back together.
Joanie develops a crush on Potsie after he sings to her at Arnold's.
J.J. is commissioned by a bank to paint a mural and in return will receive $250 needed for Thelma's college education whom recently won a scholarship and found herself $200 short. However, the bank is reluctant to pay after seeing the finished product.
A wounded colonel's gun, a showpiece, disappears, and Hawkeye and B.J. play a hunch and bluff Frank, who has it, into returning it.
The sweathogs go bananas over Bambi, a pretty blonde girl from California. We get some very funny scenes of the guys in various costumes: Epstein as a guru, Freddy in a colorful shirt, Horshack as a movie producer, and Vinnie as a surfer. When Mr. Kotter gets fed-up with them disrupting the class, it's revealed that Bambi was just pretending to be from California in order to get attention.
Archie gets a lesson in civil liberties when he's arrested using outlawed tear gas to protect himself against a mugger.
Scientist Leon Jackson defected to the Soviet Union for the love of a woman but now wants to return to the states with his son Alex.
A man steals a tugboat laden with explosives and threatens to blow up a famous marine biologist unless he is given a million dollars.
Ted is overjoyed when he gets a tax refund and splurges out on everyone at the newsroom, but is later shocked when the IRS informs him that he will be audited.
The Doctor suspects Crayford brought something to Earth in his rocket, as he and Sarah find themselves hunted by UNIT.
Bob suffers family problems when his mother becomes a houseguest and an elderly patient involves him in a parent-child vendetta.
George needs a new manager for his store on the first floor in the apartment building. However, the person who's the most qualified for the job he refuses to hire for two reasons, she's a woman and she's white.
The crew of Los Angeles County Fire Department Station 51, particularly the paramedic team, and Rampart Hospital respond to emergencies in their operating area.