When Johnny Flood, insurance investigator, overhears Burt Hobson and Garth Briggs planning the biggest bank hit in history. They catch Johnny and try to kill him. Johnny escapes, but is so badly wounded he can tell Robin Scott only a few facts about the vault job before he dies. Laurie Tibbs, Johnny's fiancee, holds Robin responsible for Johnny's death. She resolves to kill Robin--as do Hobson and Briggs, who learn Johnny talked to Robin before Johnny died. Robin barely escapes Laurie's bullet, and induces Laurie to aid him in the search for the men who killed Johnny. Laurie very nearly pays for her cooperation with her life. And Robin guesses wrong about the vault job. Ironically, it's Robin's wrong guess that gives him the right answer and leads him to the crooks just in time.