The Spanish merchant "Mare Nostrum", captained by Ulises Ferragut, docked in September 1939 at the port of Naples to repair a breakdown. Walking through the ruins of Pompeii, Ferragut meets Freyra, an enigmatic and beautiful woman of whom she instantly falls madly in love, unaware that the girl is in fact a dangerous spy of the Third Reich.
María Félix
Fernando Rey
José Nieto
Juan Espantaleón
Porfiria Sanchiz
Eduardo Fajardo
Ángel de Andrés
Guillermo Marín
Rafael Romero Marchent
Nerio Bernardi
Osvaldo Genazzani
Arturo Marín
Félix Fernández
José Franco
José Prada