In Los Angeles in 1928, single mother Christine Collins returns home to discover her nine-year-old son, Walter, is missing. Reverend Gustav Briegleb publicizes Christine's plight and rails against the Los Angeles Police Department (LAPD) for its incompetence, corruption and the extrajudicial punishment meted out by its "Gun Squad" led by Chief James E. Davis. Several months after Walter's disappearance, the LAPD tells Christine that the boy has been found alive. Believing the positive publicity will negate recent criticism of the department, the LAPD organizes a public reunion. Although "Walter" claims he is Christine's son, she says he is not. Captain J. J. Jones, the head of the LAPD's Juvenile Division, insists the boy is Walter and pressures Christine into taking him home "on a trial basis".