It could have been a Danzigers Prod or even Butchers'Company, the most prolific movie productions in terms of crime B films in UK, during fifties and sixties. Most in black and white, very short, but unfortunately not always interesting, only seldom. This one makes no exception, the tale of an undercover beat cop in a predictable and boring story. But if you crave for this genre, no matter quality, but only atmosphere, OK, that's probably for you.
Review of Crossroads to Crime
