Plot
During World War II, newly commissioned Ensign Willis Seward "Willie" Keith reports to the minesweeper USS Caine, where he meets career officer Lieutenant Stephen Maryk, the ship’s executive officer, and aspiring novelist and communications officer Lieutenant Thomas Keefer. Soon after, Lieutenant Commander Philip Francis Queeg is assigned command of the Caine. The eccentric Queeg imposes strict discipline on the lax crew, making him unpopular with them, but initially admired by Keith.
During a gunnery target towing exercise, Queeg is distracted berating Keith and Keefer over a crewman’s appearance, resulting in the ship steering over and cutting the towline, setting the target adrift. Queeg tries to cover up the incident.
Assigned to escort a group of landing craft during an invasion of a small Pacific island, Queeg abandons his mission before he reaches the designated departure point, and instead orders the dropping of a yellow dye marker, leaving the crew of the landing craft to fend for themselves. Queeg asks his officers for their support, but they remain silent and nickname him "Old Yellowstain", implying cowardice.
Believing Queeg to be paranoid, Keefer encourages Maryk to consider relieving Queeg on the basis of mental incapacity under Article 184 of Navy Regulations. Though Maryk angrily rejects that possibility, he does begin keeping a medical log documenting the captain's behavior.
Attempting to justify a strict need for discipline onboard, where even small infractions matter to maintain order, Queeg relates to his officers an account on a previous assignment where he received a commendation for an investigation to stop pilfering that involved stolen supplies of cheese. When a quart of strawberries go missing from the officers' mess, Queeg convenes an elaborate investigation to determine the culprit. Even though the mess stewards confess to having helped themselves to the missing portions, Queeg orders the berths searched and crew members strip searched. Convinced of Queeg's instability, trying to relive past “glory”, Keefer again urges Maryk to expose Queeg’s unfitness for duty. Maryk asks Keefer and Keith to go with him to report to Admiral Halsey about the matter. Arriving aboard Halsey's flagship, Keefer backs down, warning of the danger of accusing a captain, and they return to the ship.
At the height of a typhoon, Maryk urges the captain to reverse course into the wind and take on ballast, but Queeg refuses and virtually freezes up on the bridge. Supported by Keith, Maryk relieves Queeg of command under Article 184. The Caine returns to San Francisco, where Maryk and Keith face a court-martial for mutiny. Lieutenant Barney Greenwald, a temporarily grounded naval aviator and an attorney before entering the Navy, becomes Maryk's defense counsel.
At the court-martial, Keefer testifies that he never observed any mental illness in Queeg and was "flabbergasted" when Queeg was relieved. Later, when Queeg takes the stand, he exhibits odd behavior under Greenwald's relentless cross-examination, including his habit of rolling two steel balls in his hand manifesting his mental instability. Maryk is acquitted.
Following the acquittal, the officers of the Caine hold a party, where Keefer receives a frosty reception from Maryk. A drunken Greenwald arrives, remorseful about having had to expose Queeg to defend the wrongly accused Maryk instead of the man who should have been held accountable. He berates all the officers for not taking into account Queeg's long service and for failing to give Queeg the support he asked for, instead of deriding him as an incompetent. Greenwald claims their mistreatment of Queeg, who had been suffering from "battle fatigue" from his previous combat service in the Atlantic, caused the captain to become indecisive during the typhoon. He denounces Keefer as the real "author" of the mutiny, exposing to all present how Keefer disclaimed in his testimony his repeated unqualified "diagnosis" of Queeg's mental illness. Greenwald throws a glass of champagne, the "yellow wine", in Keefer's face. The rest of the officers walk out, leaving Keefer alone in the room.
Later married to his girlfriend, May Wynn, Keith is promoted to Lieutenant (junior grade), and assigned to a new Allen M. Sumner-class destroyer commanded by now-Commander De Vriess, his first captain on the Caine.
