When cat-hating Sam threatens Clinker, Perry steps in and learns Laxter's death was suspicious and the family fortune and diamonds are missing.

[1] Ricardo Cortez and June Travis take over from Warren William and Claire Dodd as criminal attorney Perry Mason and his faithful secretary Della Street respectively.

"[5] William Boehnel of the New York Herald Tribune found it to be "probably the least effective of all the Perry Mason detective films [...] A mediocre story to begin with, it is not only developed with a minimum of suspense and thrills" and declared it so confusing at times that it would take Sam Spade, Bill Crane and Reggie Fortune, Charlie Chan, Lord Peter Wimsey and Phil Vance to "piece it together convincingly.

"[5] From retrospective reviews, Pitts stated that the film will be "a disappointment to horror fans, The Case of the Black Cat is a fairly pleasing mystery.

"[7] Wollstein continued that Ricardo Cortez "makes a fine Mason, closer, perhaps, to Erle Stanley Garner's original character than his suave predecessor, Warren William."