Shack Out on 101 (1955), directed by Edward Dein.
A mostly ridiculous "thriller" with dialogue verging on the hysterical. Written by the director and his wife.
The reason to see it is for fourth-billed Lee Marvin, who dominates every scene as "Slob", a short-order cook who steals atomic secrets on the side. Vulgar lecher, comical body builder, dangerous Mr Big: he can do it all. He has an absurd friends-and-enemies buddy routine with Keenan Wynn: they're going to Muscle Beach to impress the girls but don't want to bulk up too much.
Available on Blu-ray from Olive Films.