Sealed Cargo (1951)

A Newfoundland fishingboat comes to the aid of a wrecked Danish sailing ship and tows it to a small village but eventually the captain of the fishingboat realises that its a Uboat supply ship in disguise loaded with torpedoes So together with his crew and a group of villagers he sets about a plan to blow the ship as well as any Uboats that approach it Based on the novel The Gaunt Woman by Edmund Gilligan