The story is told through the eyes of Willis Seward "Willie" Keith, a callow young graduate of
Princeton University. Following a mediocre living as a nightclub piano player, he signs up for
midshipman school at
Columbia University with the
United States Navy to avoid being drafted into the
United States Army during
World War II. He endures inner conflicts over his relationships with his domineering mother and with May Wynn, a beautiful red-haired
nightclub singer, the daughter of Italian immigrants, whom he accompanies on piano in their nightclub performances. After barely surviving a series of misadventures that earn him the highest number of demerits in his class, Keith is commissioned as an
ensign in the Naval Reserve and assigned to the
destroyer minesweeper U.S.S.
Caine, an obsolete warship converted from a post-
World War I-era destroyer. Arriving late to Hawaii, Keith misses his ship when it leaves on a combat assignment. While waiting for transportation to catch up with it, he plays piano in the evenings for an
admiral who takes a shine to him. Finally galvanized after reading a last letter from his father, who has died of
melanoma, Keith reports aboard the
Caine. The ensign immediately disapproves of the ship's decaying condition and slovenly crew. He attributes these conditions to a slackness of discipline by the ship's longtime captain,
Lieutenant Commander William De Vriess. Keith and another ensign are consigned to a miserably small and overheated shack on deck, and stumble through their early days on board. Keith's lackadaisical attitude toward what he considers menial duties brings about a humiliating clash with De Vriess when Keith forgets to decode a time-sensitive communiqué. Shortly thereafter, De Vriess is relieved, after over five years at the helm of the
Caine, by Lieutenant Commander Philip Francis Queeg, a strong, by-the-book figure, whom Keith at first believes to be just what the rusty
Caine and its rough-necked crew needs. Queeg, though, has never handled a ship like this before, and he soon makes errors of judgement that he is unwilling to admit, finding ways to lay blame on others. The
Caine is sent to
San Francisco for an overhaul, which is interrupted by orders to return to Pearl Harbor, Hawaii, for further assignment. Before the ship departs, Queeg browbeats his officers into selling their liquor rations to him, and in a breach of regulations, smuggles the liquor off the ship. When the crate is inadvertently lost overboard during the transition, Queeg
blackmails Keith into paying for it. While on leave, Keith sees May Wynn, who is now working on achieving her degree at
Hunter College, in addition to continuing to perform as a singer, and they spend a romantic weekend together in
Yosemite. Keith is still divided between his love for her and her lower social class. He resolves to let the relationship die when his leave is over by not replying to her letters. As the
Caine begins its missions in the Pacific under his command, Queeg begins to lose the respect of the crew and the loyalty of the wardroom through a series of increasingly unusual incidents, including running over and severing the cable to a valuable
towed gunnery target, which he blames on John Stilwell, the
helmsman; this reveals his cowardice, paranoia, and inability to accept responsibility. Queeg becomes increasingly isolated from the other officers, who come to dread his rages and unreasonable demands, which often entail loss of leave privileges, and at one low point, a 48-hour moratorium on drinking water while the ship is sweltering near the equator. Keith realizes that De Vriess was a far more competent, effective, and fair-minded leader, and inwardly regrets his original, naive judgements of both captains. During the following
invasion of Kwajalein, Queeg is ordered to escort low-lying
landing craft to their
line of departure. Instead, Queeg orders the crew to throw over a yellow dye marker to mark the spot, and hastily directs the
Caine away from the battle area. The officers nickname him "Old Yellowstain." Prior to the
Caine's arrival in San Francisco, Queeg had confined Stilwell to the ship for six months after catching him reading while on watch, a punishment that Keith and other officers regarded as excessive. In San Francisco, Stilwell arranges to have a relative send him a telegram faking a death in his family. Keith and executive officer Lieutenant Stephen Maryk see through Stilwell's ruse, but nevertheless allow him a shore leave pass, contradicting Queeg's orders. Suspicious of Stilwell's excuse, Queeg requests the Red Cross confirm the death. Months later, the Red Cross exposes Stilwell's lie, and Queeg orders him court-martialed by Keith and two other officers, making it clear to them that he wants Stilwell to receive a
bad conduct discharge from the Navy. Instead, the three officers give Stilwell an extremely minor punishment, enraging Queeg and leading him to institute punitive measures against the ship's officers. Queeg's next act of paranoia begins when over half of a prized container of strawberries is discovered to be empty. He concocts elaborate and time-consuming procedures in which to catch the thief. These occupy all of the officers and crew for long hours and further erode confidence in and respect for the captain. When Queeg's pet theory is finally decisively flouted, he disappears into his cabin, leaving the ship in Maryk's hands for days. The intellectual communications officer, Lieutenant Tom Keefer, who coined the "Yellowstain" nickname, suggests to Maryk that Queeg might be mentally ill. Keefer directs Maryk to "Section 184" of the
Navy Regulations, under which a subordinate can relieve a commanding officer in extraordinary circumstances. Maryk, a dutiful and dependable executive officer who brooks no public criticisms of Queeg, nevertheless begins to keep a secret log of Queeg's actions, and ultimately decides to bring them to the attention of Admiral
Halsey, commanding the
Third Fleet, when Halsey's
flagship and the
Caine are anchored at the
Ulithi atoll. Keefer agrees to accompany Maryk, but then gets cold feet and backs out, and both men return to their ship without ever meeting the admiral. Soon afterward, the
Caine is caught in
Typhoon Cobra, an ordeal that sinks three destroyers and threatens to overwhelm the
Caine. At the height of the storm, Queeg's paralysis convinces Maryk that he must relieve the captain of command to prevent the loss of the ship. Keith, as
officer of the deck, supports the decision. Maryk turns
Caine into the wind and rides out the storm. Maryk is tried by
court-martial for "
conduct to the prejudice of good order and discipline" instead of "making a mutiny". Keith and Stilwell,
helmsman during the typhoon, are also to be tried, depending on the outcome of Maryk's trial. In the courtroom, Keefer distances himself from any responsibility for the relief of command from Queeg. Lieutenant Barney Greenwald, a
naval aviator who is an attorney in civilian life, represents Maryk. Greenwald's opinion, after Queeg is found to be sane by three Navy
psychiatrists, is that Maryk was legally unjustified in relieving Queeg, but he decides to take the case after deducing Keefer's background role in the crisis. During the trial, Greenwald unrelentingly cross-examines Queeg until the increasingly defensive Queeg starts to display the erratic and unreasonable behavior that the officers had previously reported. Queeg's performance results in Maryk's acquittal and the dropping of charges against Keith and Stilwell. Maryk, who had aspired to a career in the
regular Navy, is sent to command a
landing craft infantry, a humiliation that ruins his naval career ambitions. Queeg is transferred to a naval supply depot in Iowa. At a party celebrating both the acquittal and Keefer's success at selling his novel to a publisher, an intoxicated Greenwald arrives late, and calls Keefer out as a coward. He tells the gathering that he feels ashamed of having destroyed Queeg on the stand because Queeg and all other regular armed-forces officers have performed the necessary duty of guarding America in peacetime, which Keefer and others view as work that is beneath them. Greenwald states that the officers' disdain and disrespect for Queeg is what led to his inability to take action during the typhoon. Greenwald concludes by saying that officers like Queeg kept Greenwald's Jewish mother from being "
melted down into a bar of soap" by the Nazis. He calls Keefer, not Maryk, "the true author of 'The
Caine Mutiny,'" and throws a glass of champagne, "the
yellow wine", into Keefer's face — bringing the term "Old Yellowstain" full circle. Keith returns to the
Caine during the last days of the
Okinawa campaign as its executive officer. Keefer is now the captain, and his behavior as captain is similar to Queeg's. The
Caine is struck by a
kamikaze, an event in which Keith discovers that he has matured into a naval officer. Keefer panics and orders the ship abandoned, but Keith remains aboard and calmly rescues the situation by heroically dousing the fires. Keefer, discharged after the war ends, is ashamed of his cowardly behavior during the kamikaze attack, especially because his half-brother Roland has died saving his own ship, also from kamikaze fire. Keith is promoted as captain of the
Caine. He receives a
Bronze Star Medal for his actions following the kamikaze explosion, and a
letter of reprimand for his part in supporting the unlawful relief of Queeg. The findings of the court-martial are overturned after a review by higher naval authorities, but Keith, in retrospect, agrees that their actions were legally unjustified and probably unnecessary. Captain Keith keeps the
Caine afloat during another typhoon and brings it to
Bayonne, New Jersey, for decommissioning after the end of the war. His first desire and primary aim upon departing the
Caine and the conclusion of his duties is to find May Wynn and ask her to marry him. His wartime experiences have finally crystallized his desire and decision, but over a year and a half have passed since they last saw each other. He discovers she is in a musical and romantic partnership with a popular bandleader, has dyed her hair, and is now performing under her real name, Marie Minotti. Keith surprises her when he appears unexpectedly at the club where she performs, and makes his case with ardent conviction. The book ends with their romantic situation unresolved; Minotti must put her past heartbreak over Keith, as well as her current relationship behind her, and assess whether she can trust what her heart tells her, but the reader is left with the sense that the two will finally unite, and the book closes as confetti from the victory parade in the streets settles on the shoulders of the last captain of the
Caine. ==Historical background==