Scott Harper is a frustrated police detective who is constantly passed over for promotion. When he is assigned to gain the confidence of Holly, the girlfriend of a robbery suspect, the couple fall in love and then plot to murder Holly's boyfriend and run off to Mexico with the loot.
In a contemporary review for the New York Daily News, critic Maxine Dowling called Cage of Evil "a bitter and contrived tale...It's an uninteresting, slowly paced melodrama that does nothing for anyone concerned, least of all our much maligned police."[3]
The New York Post commented that "performances are better than fair," and that the film "is a shoot-it-out opus with little surprise. The audience knows from the beginning that detective Ron Foster is unhappy with his lot. Much work, no promotion. We wait for him, on the trail of a diamond thief, to go over to the other side. This he does, not only because he envies the spoils, but because he has fallen for the crook's moll, Pat Blair. They get theirs!"[4]
TV Guide wrote that "it's not bad for grade-B crime drama."[5]