Street of Sinners [1957] [DVD]

from IMDB: John (George Montgomery) is a rookie cop about to start his first beat. However, he is quite naive and knows little about the neighborhood and the hood who runs it. Leon (Nehemiah Persoff) is a small-time mobster who has connections in City Hall....and for years, folks have ignored Leon. But while at first Leon seems like a minor crook who isn't doing much harm, his influence goes far beyond just serving liquor to underage kids in his bar. Can John manage to stand up to Leon and both keep his job AND not get his head blown off as well? And, can John effect change when his fellow officers don't seem to care?

Despite the film initially seeming pretty cheesy and stiff, the film improves as you watch. It soon becomes tense and exciting....and leads to a dandy finale. Well made and very well written.