In "Murder On Flight 502" a group of diverse passengers embark on a transatlantic flight from New York to London. A few of the travelers are a washed-up rock band performer, a thief, a priest, a mystery writer and a doctor (Ralph Bellamy) who helps a passenger having a heart attack. As they are boarding the plane, an unforgiving father sees that the man he suspects of murdering his daughter, Jack Marshall, (Sonny Bono) is taking the same flight. Just after the flight takes off, NYC airport security radioes the jet's level-headed pilot, Larkin, (Robert Stack) informing him of a suspicious-looking package that might be a bomb. But that turns out to be nothing but a prank. Millard Kensington, (Danny Bonaduce) a boy on flight 502, admits he left a smoke bomb in the airport lounge just to scare people. A little later, security calls Larkin again, this time with a much more urgent matter. A menacing note is found in the airport signed by someone claiming to be one of the passengers aboard flight 502. This troublemaker says that there are going to be people on the flight who will be murdered before touch down in London. They are unsure whether this note will turn out to be a prank like the smoke bomb was, but when a passenger is killed onboard the flight, Detective Daniel Myerson (Hugh O'Brian) begins investigating the passenger list and finds some interesting connections between some of them. Flight attendant Karen White (Farrah Fawcett-Majors) does her best to stay cool as a cucumber to keep all the passengers from becoming panicky while she tries to identify the killer.