Dyavolskoto orazhie (1982)

The nineteenth century. Batil is a young boyar. An envoy of the Bulgarian tsar comes to him with a request to open the secret weapon of the Savoyans. Together with two friends, he infiltrates the fortress of Amedee of Savoy and frees the boyar Dragot and his daughter Radusha from captivity. Batil manages to capture the knight Roland, and he learns what is actually a "devil" weapon. It's gunpowder. Radusha helps Bathil and his friends sink a ship carrying gunpowder. She decided to stay with Batil forever.