Elisabeth is a wealthy woman who is reaching her forties. She travels regularly on the TEE Rheingold train. One day, she meets a former school flirt, who works as a flight attendant on the train.

A mature, rich and bored woman called Elisabeth is taking a ride with the "Rheingold", a first-class high-speed train of the seventies along the river Rhine. In the train she is meeting her old school mate and lover who is working as a waiter and falls in love with him again. Her husband, a busy politician, realizes what's going on and tries to catch the train to face his wife and her lover in a fatal showdown.