The Second World War is remembered for its colossal battles in the air, on land and at sea. But perhaps the most terrifying were those waged UNDER the ocean, against an unseen enemy. By the end of 1941, cumbersome shipping convoys were Britain's only lifeline. Protecting them proved a difficult task, and German U-boats hunting in wolf packs sank merchant ships faster than they could be built. But into this loosing battle stepped the British naval officer and pioneer of anti-submarine warfare, Frederic 'Johnnie' Walker.

Dan is joined by Angus Konstam, author of The Convoy, to take us through the remarkable story of Convoy HG-76, and explain how Captain Walker turned the hunted into the hunters.

Produced by James Hickmann and edited by Ella Blaxill.

Discover the past with exclusive history documentaries and ad-free podcasts presented by world-renowned historians from History Hit. Watch them on your smart TV or on the go with your mobile device. Get 50% off your first 3 months with code DANSNOW sign up now for your 14-day free trial.

We'd love to hear from you! You can email the podcast at ds.hh@historyhit.com">ds.hh@historyhit.com.

You can take part in our listener survey here.