Fernando Porredón

Cristina Guzmán is hired to impersonate the disappeared sister-in-law of a rich man.

A newly remarried widow is accused of having murdered her first husband, who died from arsenical poisoning. Being her present husband a lawyer he takes charge of her defense.

Due to a rail accident, the passengers of a train had to be housed in a nearby town while awaiting the arrival of a relief convoy. In the train were traveling Alicia and Paul, a couple who will marry soon, along with her ​​mother, and George, a mature man who looks for a woman he loved. Due to the accident, they will have to spend the night there, where chance lead to a series of events that make the passengers no longer be the same.