This time the evil foreign spy is a woman and the documents are blueprints for a new submarine. Francesca Bertini as Helene, the self-sacrificing wife of wrongly-suspected submarine engineer Waldor, is upstaged by Mary-Cléo Tarlarini as the criminal Princess Silestra. The unscrupulous baddie rains bullets around the lounge and starts a magnificent final conflagration intended to kill the beauty. Cue last-minute rescue. The second half of this – a diva film with the features of an action adventure and a great villainess – was found and identified in the BFI collection.