Submarine X-1 (1968)

During World War II, Captain Cassidy and his crew of submariners are ordered into Tokyo Bay on a secret mission. They are to gather information in advance of the planned bombing of Tokyo. Along the way, the crew learn about each other as they face the enemy and some of them lose their lives.

During WWII, Duke E. Gifford is second in command of the USS Thunderfish, a submarine which is firing off torpedoes that either explode too early or never explode at all. It's a dilemma that he'll eventually take up personally. Even more personal is his quest to win back his ex-wife, a nurse; but he'll have to win her back from a navy flier who also happens to be his commander's little brother.

At the height of Hitler's infamous U-boat war, the crew of the U.S.S. Swordfish were heading home after months at sea. They never made it. Now prisoners of war aboard U-boat 429, a small group of American survivors will find their loyalties put to the ultimate test when they're forced to join their German captors to fight for their very lives.

In the midst of World War II, the battle under the sea rages and the Nazis have the upper hand as the Allies are unable to crack their war codes. However, after a wrecked U-boat sends out an SOS signal, the Allies realise this is their chance to seize the 'enigma coding machine'.

At the start of World War II, Cmdr. Ericson is assigned to convoy escort HMS Compass Rose with inexperienced officers and men just out of training. The winter seas make life miserable enough, but the men must also harden themselves to rescuing survivors of U-Boat attacks, while seldom able to strike back. Traumatic events afloat and ashore create a warm bond between the skipper and his first officer.

Mr. Roberts is a Navy officer who's yearning for battle but is stuck in the backwaters of World War II on a non-commissioned ship run by the bullying Captain Morton.

The haunted Captain of a Soviet submarine holds the fate of the world in his hands. Forced to leave his family behind, he is charged with leading a covert mission cloaked in mystery.

When a Soviet submarine gets stuck on a sandbar off the coast of a New England island, its commander orders his second-in-command, Lieutenant Rozanov, to get them moving again before there is an international incident. Rozanov seeks assistance from the island locals, including the police chief and a vacationing television writer, while trying to allay their fears of a Communist invasion by claiming he and his crew are Norwegian sailors.

Sent to rescue survivors from the site of a plane crash in the South Pacific during WWII, Captain Kelly and his elite squad of Australian commandos must keep tabs on a defecting Japanese official who could hold the secret to peace.

A first-time captain leads a convoy of allied ships carrying thousands of soldiers across the treacherous waters of the "Black Pit" to the front lines of WWII. With no air cover protection for 5 days, the captain and his convoy must battle the surrounding enemy Nazi U-boats in order to give the allies a chance to win the war.