The Incredible Mr. Limpet

In 1963, George Stickle and Admiral Harlock discuss the peculiar abilities of porpoises and speculate that Henry Limpet, a former top-secret asset, may be guiding them. The conversation frames Limpet as a legendary figure whose deeds are still a mystery. This scene sets the ongoing question of Limpet's influence at sea.

Henry Limpet is a shy bookkeeper who loves fish and longs to join the Navy. He is rejected as 4F because of his poor eyesight and other reasons, while his wife Bessie is fiercely patriotic. The contrast establishes Limpet's yearning and the wartime context.

During a leave, Limpet and George visit Coney Island, where Limpet falls into the water and inexplicably becomes a fish. He never resurfaces, and Bessie and George assume he has drowned. The upheaval marks the start of his underwater life.

As a fish, Limpet discovers a powerful underwater roar, his thrum, and befriends Crusty, a misanthropic hermit crab. He also encounters a female fish he names Ladyfish, with whom he forms a complicated bond. The transformations drive his secret life in the ocean.

After the attack on Pearl Harbor, Limpet directs a Navy convoy to a nearby German U-boat using his thrum. His unusual ability immediately proves useful to wartime operations. The event marks the start of his active service and integration with the Navy.

With George's help, Limpet is commissioned by the Navy, earning an advanced rank and a salary. He sends the earnings to Bessie, maintaining their connection despite his amphibious life. This formalizes his service and commitment to the war.

Limpet uses his thrum to signal the Navy and locate Nazi U-boats, becoming an invaluable asset in the Atlantic theater. His unique talents help sailors track subs with greater efficiency. He becomes a symbol of unlikely heroism.

He plays a large part in the Allied victory during the Battle of the Atlantic, coordinating submarine hunts and protecting convoys from U-boat attacks. His actions change the course of several missions and boost morale aboard allied ships. The war drama expands beyond land into the ocean.

The Nazis develop a thrum-seeking torpedo that nearly kills Limpet, intensifying the peril of his mission. He is further handicapped by the loss of his spectacles, complicating his navigation.

Unable to rely on sight, Limpet relies on Crusty the crab as his navigator and continues to guide his vessel. He sinks U-boats by redirecting their torpedoes, turning a near-fatal situation into a tactical victory.

After the battle, Limpet swims to Coney Island to bid farewell to Bessie, who provides him replacement glasses. He then chooses to swim off with Ladyfish, stepping away from human life but returning to the sea.

In the film's coda, back in 1963, George and the Admiral travel out to sea to contact Limpet about whether he is training the porpoises. The scene preserves the mystery around Limpet's ongoing life and the potential ongoing bond with the ocean.