After serving time in Sing Sing, Eddie Ellison marries his fiancée Kay Ellison and the couple soon welcomes a daughter they name Shirley Ellison. Life looks hopeful for the small family as Eddie tries to build a steady future, while Kay supports him with quiet strength. Eddie also helps a friend, Larry Scott, who is engaged to Jane, by helping him land a job as a chauffeur for the factory owner Mr. Carson. The arrangement seems straightforward, but underneath the surface, old ghosts linger and threaten to disrupt the fragile peace they’ve begun to create.
Trouble erupts when Trigger Stone, another ex-con, steals Mrs. Carson's pearl necklace and tries to rope Eddie and Larry into selling it. They refuse, sensing the danger and the risk of dragging their families back into trouble. The incident sets off a chain reaction: Welch, the private investigator Welch who once helped convict Eddie, informs the head of the National Insurance Company that Eddie and Larry might be involved, and he passes this warning to Mr. Carson. Fearful for his business and his own reputation, Carson fires the two chauffeurs, tightening the net around Eddie and Larry and widening the shadow over their lives.
As the tension escalates, Trigger hatches a desperate plan to outrun the consequences. He passes the necklace to Shirley, who believes it is a belated birthday present, a small spark of mischief that tests the boundaries of trust within the family. In a rash moment of play, she hides the necklace in her father’s pocket, and when Eddie discovers it during a sweep of the apartment, he stashes it away in the carpet sweeper to keep it out of sight. Yet the delicate thread of safety begins to unravel when the neighbor’s maid Anna borrows the sweeper and, unknowingly, empties it, leaving no clue as to the necklace’s whereabouts when she returns it.
The homeward return of Kay triggers a frantic scramble to uncover the truth. Welch returns at one point and opens the apartment’s carpet sweeper, only to find it empty, a moment that heightens the sense of danger pressing in on them. With Welch gone, Eddie, Larry, Kay, and Jane embark on a tense search through the apartment building, wary of every odd noise and shadow that might announce Trigger’s presence or the necklace’s fate. When Trigger confronts Eddie with a gun, a struggle ensues. Eddie manages to subdue him, tie him up, and step out to summon help, but the danger is far from over.
In a cruel reversal of fortune, Shirley discovers the necklace in a garbage can downstairs. She runs to Eddie with the hope of sharing the luck, but instead she encounters Trigger again, who persuades her to release him. He snatches the girl and makes a perilous climb to the roof, forcing a desperate pursuit. A violent confrontation follows: Trigger shoots Eddie, injuring him, but Eddie fights back with resilience and ultimately captures Trigger. Back on the ground, Shirley retrieves the necklace from Trigger’s pocket, and the case takes a decisive turn when detective Flannigan informs her that she will be eligible for the $5,000 reward. The tension of the pursuit gives way to a hard-won sense of closure as the pieces fall into place and the family learns how luck and luck’s absence shape the fate of a small, hopeful unit caught in the gears of crime and consequence.
