Nuclear Family was the 21st episode of Season 3 of Quantum Leap, also the 52nd overall episode in the series. Written by Paul Brown, the episode, which was directed by James Whitmore, Jr. first aired on NBC-TV on May 15, 1991.
Sam must deal with the panic associated with the Cuban Missile Crisis as a Florida fallout shelter salesman.
Sam leaps into Eddie Elroy in the middle of the Cuban Missile Crisis. Sam was very young at the time and cannot understand everyone's panic that the Russians are going to kill them all. Al remembers that time very well (he flew missions during that time) and tries to explain it but it is something that had to be lived through to be understood.
Eddie lives with his brother's family and helps sell fallout shelters to put himself through school. Sam already dislikes the constant fear everyone lives in but it gets worse when he discovers that the brother "Mac" (played by Timothy Carhart) shoots and kills one of his neighbors during a false alarm when the man tries to break into his fallout shelter.
Sam tries to reassure at least the children that they're not going to die but they get even more upset when he tries to say that the Russians don't want to kill them. The daughter is convinced disagreeing with her father means that Sam is calling her father a liar and is hysterical. Sam has more luck with his sister-in-law in that she doesn't burst into tears and run from him but she is still unconvinced that they will survive.
Because Sam knows that fallout shelters would be useless even if something were to happen, he does not have much luck selling them. He tries to get the neighbor destined to be shot Burt (played by Kurt Fuller) to not buy a shelter but Burt is adamant. He also manages to convince the children's piano teacher not to buy one because she and her husband cannot afford one. As she is a Holocaust survivor, he cannot convince her that she is safe but that with so little time left there is no point in wasting her money.
Mac gets angry and threatens to kick Eddie out for sabotaging sales and for scaring his children. Sam decides to take matters into his own hands and buries the bullets from the fallout shelter so that Mac can't shoot Burt. The family dog digs up the shells, however, and Mac and Sam narrowly manage to get them back. Mac knows that it was Eddie and tries to kick Sam out of the house but he won't leave until he saves Burt.
Things come to a head as the family is watching a presidential bulletin when someone panics and initiates a blackout. Convinced that the end has come, the family goes down into the fall-out shelter. Since Burt's shelter has yet to be built, he tries to break into the shelter and Mac holds him off with a gun (although he insists to his wife he is just scaring him). Al realizes that Mac has the wrong gun to have shot Burt and son Stevie took the right gun and snuck out the other exit to the bunker. He is so terrified that he sees his neighbor as an invading Russian and Al realizes that he must have always been the shooter and Mac felt so guilty that he took the blame. Sam climbs up and tries to talk Stevie down. Stevie recognizes his uncle but doesn't listen. Desperately, Sam recalls one of the cartoons Stevie was watching about what to do when a nuclear bomb hits and gets Stevie to duck and cover so he can grab the gun.
When the crisis is over, Mac realizes that Sam was right and thanks him for stopping Stevie, allowing him to stay. Everyone cancels their fallout shelter orders and Mac is upset because he already has all the construction equipment. Sam suggests they go into the pool installation business. Al laughs that off but then checks and realizes that Mac and Eddie have a very successful pool company.