Dick Van Dyke plays a deranged man who plans to repay a kindness by killing the estranged wife of his benefactor.
Paul Sand guest stars as a young reporter who falls for a mysterious passenger. He is unaware that she is a crown princess who is being stalked by two assassins with a mission to see that she does not get off the Supertrain alive.
A presidential candidate is secretly abducted by his identical twin—a man anxious to pose as his office-seeking brother.
Film producer Jack Hogarth has to convince his ex-wife, movie star Tammy Tyler, to star in his latest picture to get two mob enforcers off his back. Problem is, Tammy and the two goons have boarded Supertrain, but he hasn't.
Despite having professional protection, recent heiress Natalie Smithburne finds herself on the run from former servants. When she bumps into shy gynecologist Marshall Fossberg, she convinces him to stay with him in his cabin.
Harry Flood gets the mumps, so his new Executive Operations Officer, Wayne Randall, has to take over on his maiden trip aboard the Supertrain. Penny Whitaker is overseeing Audrey Fuller's fashion show when a emerald necklace is stolen.
Supertrain hosts the televised International Poker Championship. Five of the world's best players compete, but one has been replaced by a mysterious woman.
A murder suspect and his minder, a women's magazine writer, a honeymooning couple and a pregnant woman get involved in an impromptu hostage situation on Supertrain.