It has been exhibited both as a theatrical release and a TV miniseries Several different home video versions, as well as a director's cut supervised by Petersen, have also been released. It depicts both the excitement of battle and the tedium of the fruitless hunt, and shows the men serving aboard U-boats as ordinary individuals with a desire to do their best for their comrades and their country.
Development began in Several American directors were considered three years earlier, before the film was shelved. During production, Heinrich Lehmann-Willenbrock , the captain of the real U during Buchheim's patrol and one of Germany's top U-boat "tonnage aces" during the war, and Hans-Joachim Krug, former first officer on U , served as consultants. One of Petersen's goals was to guide the audience through "a journey to the edge of the mind" the film's German tagline Eine Reise ans Ende des Verstandes , showing "what war is all about".
Lieutenant Werner, a war correspondent on the German submarine U in October , is driven by her captain and chief engineer to a French bordello, where he meets some of the crew. Thomsen, another captain, gives a drunken speech to celebrate his Ritterkreuz award and mocks Adolf Hitler. The next morning, U sails out of the harbour of La Rochelle , and Werner is given a tour of the boat.
He observes ideological differences between the new crew members and the hardened veterans, particularly the captain, who is cynical about the war. The new men, including Werner, are mocked by the rest, who share a tight bond. One Nazi officer, 1-WO the first [watch] officer , is disliked due to his pro-Nazi beliefs and meticulous grooming habits, which tie up the only bathroom.
After days of boredom, the crew is excited by another U-boat's spotting of an enemy convoy, but they are soon spotted by a British destroyer and attacked with depth charges. They escape with light damage. The next three weeks are spent enduring relentless North Atlantic gales. Morale drops after various misfortunes, but the crew is cheered by a chance encounter with Thomsen's boat. After the storm ends, the boat encounters a British convoy and launches three torpedoes, sinking two ships. They are spotted by a destroyer and have to dive below test depth, the submarine's rated limit.
