A man is convicted of murder but is adamant of his innocence. His brother, who is already strapped for money financing the convicted man's legal bills, tries an outrageous bluff. The brother plans to blackmail the star witness of the trial. The idea is to convince authorities the witness was the real killer. The witness, an owner of a shipyard, has his own ideas. He hires a hit man. Erskine and Colby are drawn into the case when the wife of the witness reports an extortion letter to the FBI. The question is whether the agents can solve the case before anyone else winds up dead.
—Bill Koenig