Action in the North Atlantic 1943 Humphrey Bogart, Raymond Massey, Alan Hale, Julie Bishop

World War 2 action in the North Atlantic
An American oil tanker, the SS Northern Star, commanded by Captain Steve Jarvis, is sunk in the North Atlantic Ocean by a German U-boat. Along with First Officer Joe Rossi, Jarvis boards a lifeboat, which is rammed and sunk by the U-boat that torpedoed their ship. The survivors are finally rescued after 11 days adrift on a balsa wood life raft.
During their brief liberty, Steve spends time with his wife Sarah, while Joe meets and marries singer Pearl O'Neill. At the maritime union hall, the Northern Star survivors await assignment to a new ship, which turns out to be a brand new Liberty ship, the SS Seawitch, commanded by Jarvis, with Rossi once again his First Officer.
The Seawitch, armed with anti-aircraft guns manned by trained Navy gunnery personnel, embarks with a convoy carrying vital war supplies to the Soviet port of Murmansk. However, the convoy is forced to disperse when a wolfpack of U-boats torpedoes them one by one. The Seawitch, now on her own, takes successful evasive action, hiding out at the edge of the Arctic icepack to evade a U-boat hunting her.
After the U-boat breaks off the search, Seawitch lights her boilers off again and heads for Murmansk. The Luftwaffe is called in to try and find the ship. The German maritime patrol planes locate Seawitch and attack with bombs and machine guns. In the ensuing action, Captain Jarvis is seriously wounded, and eight members of the crew and the Armed Guard force are killed. It is up to First Officer Rossi and the surviving members of the Seawitch's crew to get her to port. The fliers had reported locating the Liberty ship, and the U-boat returns to try and sink her. The submarine hits the ship with one torpedo, but Rossi fools the submarine captain into surfacing to finish off the wounded Liberty with his deck gun by setting smoky fires on deck. The Seawitch, listing and damaged, maneuvers and rams the U-boat, sinking it with all hands.
Fires out but still holed, the damaged Liberty continues to Murmansk, wondering if they can make it – which they do, thanks to a squadron of Russian fighters escorting them in. In the end, Joe Rossi, looking at what's left of the convoy in port, worries about the challenges that await them on their return trip.