After blacking out from an all-night drinking binge, a dock worker Bobo wakes up in a decrepit shack on a San Pablo Bay barge. The barge’s owner, fisherman Takeo, reminds him how they met the previous night and that he agreed to work for Takeo. Bobo does not remember the encounter and plans to leave, but a passing police boat and the news that local bar-fly Pop Kelly was murdered during his drinking spree pull him back. Fearful that he may have killed the man, Bobo decides to stay and take the job, clinging to the possibility of a clean break.
He heads into town to find his old friends, meeting up with Tiny, a brash, protective figure, and Nutsy, the town watchman with a philosophical bent, at a cramped boardinghouse. Tiny’s insistence that he didn’t hurt anyone does little to reassure Bobo, who agrees to a late-night plan to leave town with Tiny. During a stroll by the water, Nutsy discovers that Bobo is in possession of Pop Kelly’s hat, a clue that gnaws at him and foreshadows the trouble ahead.
Near the shore, a commotion draws Bobo toward a young woman who seems to be about to throw herself into the surf. He plunges in and rescues her, bringing her back to the barge. The next morning, the rescued woman—Anna—recovers, tidies the shack, and even helps Bobo repair the boat of Dr. Frank Brothers, a wealthy doctor who is accompanied by his mistress. Anna quietly begins to rebuild her life, while Tiny arrives again to taunt and belittle her, suggesting she once worked in a hash house or could be a prostitute. He argues that Bobo should disappear with him, but Anna overhears and tells Bobo she is “much obliged for everything” but she is “blowing now,” planning to return to her own path.
As the two men talk, Nutsy becomes a calm counterweight, encouraging Bobo to accept that he might want a home rather than just a restless life. Anna and Bobo grow closer, and the possibility of a future together becomes tangible. Yet the threat Tiny poses lingers, and Bobo’s violent tendencies from his past haunt him even as he acts with restraint.
The couple decides to marry on the barge, celebrating with friends as a new chapter begins. Dr. Brothers sails by and, with Anna’s blessing, the doctor leaves his mistress to reunite with his wife. On the barge, Anna opens a gift from Bobo—a gaudy revealing dress that once belonged to Mildred. Nutsy reassures her that wives should sometimes shed modesty, and Anna tries on the dress, envisioning a future where she and Bobo are truly at home together.
That night, Tiny arrives drunk and angry at not being invited to the wedding. A heated exchange reveals the depth of Tiny’s resentment, and in a violent moment he attacks Anna. When Bobo returns, he and Dr. Brothers find Anna injured, stuffed in the bait box, and they rush her to the hospital. Dr. Brothers vows to do all he can to help her. Bobo heads out to find Tiny, tracking him to the breakwater. Tiny maintains his innocence to the end, but he cannot swim, and a powerful wave carries him away.
After Anna has healed enough to leave the hospital, Bobo brings her back to the barge via the doctor’s boat. She remains unable to walk, but Bobo is eager to carry her across the threshold into the cozy home they’ve built together. As they step inside, their favorite song plays, marking the quiet, hopeful close of a nightmarish ordeal and the start of a shared life.
