The Wrecker (1933)

What did Chuck Regan do when he swung perilously above his former wife and hated rival, almost completely buried under the debris of an earthquake---their lives in his hands---when he knew that their death meant the return of his child?

The Wrecker is a flinty-eyed demolition engineer named Regan (Jack Holt). While he's off on another assignment, Regan's wife Mary (Genevieve Tobin) and supposed best friend Cummings (Sidney Blackmer) engage in some heavy petting. About to wash his hands of his faithless wife and his back-stabbing chum, our hero is compelled to save both their lives when they're pinned under the wreckage of a collapsed schoolhouse. George E. Stones supplies some good-natured ethnic humor as Regan's junk-dealer pal Shapiro.