Police Lt. Diamond is told to close his surveillance of suspected mob boss Mr. Brown because it’s costing the department too much money with no results. Diamond makes one last attempt to uncover evidence against Brown by going to Brown’s girlfriend, Susan Lowell.

Julia Ross secures employment, through a rather-noisy employment agency, with a wealthy widow, Mrs. Hughes, and goes to live at her house. Two days later, she awakens in a different house in different clothes and with a new identity. She is told she is the daughter-in-law of Mrs. Hughes and has suffered a nervous breakdown. She soon learns that the son of Mrs. Hughes, Ralph, has murdered his wife, disposed of her body and, with his mother’s help, plans to pass Julia off as his wife. And then plans to eventually kill her and pass it off as a suicide.