Enjoyable minor film noir with a good cast, tough dialog, and interesting locations. Dan Duryea and Tony Curtis (in a non-speaking role) would appear the same year in CRISS CROSS, while John McEntire and Barry Kelley would be in THE ASPHALT JUNGLE the following year. Also in the cast Shelley Winters and Howard Duff.

This is a frequently used plot of a government agent or policeman secretly infiltrating a criminal organization and it works very well with Duff and especially Duryea, playing the leads. Winters is a sympathetic call-girl and McEntire is great as a duplicitous character. The day-for-night locations in Mexico (or a stand-in for it) are dramatically shot with overhanging clouds and trees that seem to glow in the shadows. William Castle directs and he's at his best. Not a major noir by any means, but a fine film that deserves to be restored.