Although he doesn't know it at first, industrialist Walter Williams (Brian Donlevy) shouldn't trust his wife Irene (Helen Walker) any farther than he can throw her. Irene schemes with her lover Jim Torrance (Tony Barrett) to kill Walter in an "accidental" car crash (ergo, Impact). The plan fails, and it is Jim who is killed. When it develops that he is assumed to have also died in the accident, Walter changes his name and heads to a small town where no one knows him. Here he starts life all over again as a humble garage mechanic, falling in love with his boss Marsha Peters (Ella Raines) in the process. Disaster looms when detective Quincy (Charles Coburn) comes sniffing around; it seems that Lt. Quincy suspects the incognito Williams of murdering Torrance. To reveal any more would be giving the game away. Impact co-stars longtime favorite Anna May Wong, making her first screen appearance since 1942.