Rosario is unjustly condemned for a robbery committed in the Variety Theater, where she worked as secretary of businessman Gastón Leducq. When she leaves prison, she tries to prove her innocence. But then Gastón appears murdered and Rosario becomes the main suspect. Mercedes, Gastón's wife, accuses her of being the author of the crime. Then appears a stranger who blackmails Mercedes, demanding a large sum of money in exchange for the evidence that shows the innocence of Rosario, but he is murdered. The police discover the relationship between the two murders and ends up discovering the true culprit of the double crime.