In February 1945, the HMS Venturer was deployed off the coast of Norway for her eleventh patrol of the war. Mid-way through the patrol, she picked up the sound of an engine belonging to a German U-Boat.

Over the next few hours, the Venturer stalked her prey, gathering information on the course and speed of the U-Boat.

The engagement that followed would go down as the only recorded underwater submarine battle in Military history.