What Price Crime (1935)

FEDERAL AGENTS WAGE WAR ON CRIME!

Thieves break into a warehouse that stores guns, steal them and kill the night watchman. An undercover agent assigned to the case happens to get into a traffic accident with the sister of the man the police suspect is head of the burglary ring, and in order to work his way into the gang, he romances the boss' sister. Complications ensue when the two fall in love.