It is all but impossible to dislike this ultra-cheap Cold War paranoia melodrama. Virtually the entire picture takes place on a single set, representing a rundown roadside diner. Lee Marvin plays the aptly named Slob, a lecherous short-order cook who lusts after shapely waitress Kotty (Terry Moore).
Also interested in Kotty is a scientist known only as The Professor (Frank Lovejoy), who spends the better part of his free time at the diner's counter. It turns out that the Professor is a traitor, exchanging top-secret information with Slob, who's actually a commie agent.
Only the Professor isn't a traitor, see, he's really . . . But why spoil the film for the uninitiated? For the record, Keenan Wynn and Whit Bissell are also in Shack Out on 101.