Republic's The Unearthly was originally released on a double bill with The Beginning of the End. John Carradine chews the scenery as Professor Conway, who claims to have discovered a gland which enables his patients to live forever. Alas, most of Conway's human experiments are failures, left to scream and gibber in the doctor's cellar. His latest "volunteer", a beautiful neurotic named Grace (Allison Hayes), arouses Conway's libido, and as a result he is hesitant to operate upon her; the same does not apply to another patient (Sally Todd), whom Conway inadvertently transforms into a nonagenarian. Fortunately, a police officer (Myron Healey) posing as an escaped convict manages to put an end to Conway's unearthly experiments. Harry Thomas' makeup work on Dr. Conway's hideously deformed human guinea pigs is the only worthwhile aspect of The Unearthly. Tor Johnson makes another of his appearances as mute monstrosity Lobo.
~ Hal Erickson, All Movie Guide