While taking a train trip from L.A. to Chicago, mild-mannered George Caldwell (Gene Wilder) makes the acquaintance of Hilly Burns (Jill Clayburgh). As they indulge in a brief bit of spooning, Hilly tells George that her boss is on the verge of exposing a group of vicious art forgers.
Later that evening, George sees the body of Hilly's boss being thrown off of the train. Detective Sweet (Ned Beatty) agrees to investigate, but he too is bumped off. The instigator of these outrages is master forger Roger Devereau (Patrick McGoohan), who, with his crony Mr. Whiney (Ray Walston) is planning a particularly diabolical crime.
Worse still, they take Hilly prisoner so she can't tip off the cops. When George is also targeted for elimination, he manages in slapstick fashion to elude the killers. Falling off the train, he ends up being arrested on some trumped-up charge or other by a local sheriff.
He makes his escape in the company of petty thief Grover Muldoon (Richard Pryor) -- and that's only the beginning. A box-office smash, Silver Streak paved the way for the equally successful 1980 Wilder-Pryor vehicle Stir Crazy.