From "The Psychotronic Encyclopedia of Film":
The merits of this incredible film have not been exaggerated. It's not actually the worst film ever made, but it's the most entertaining bad one you'll ever find. The story was built around a few minutes of Bela Lugosi footage shot days before he died (in '56). The scene of old Bela visiting the grave of an imaginary dead wife is really pretty sad to watch. But as soon as aliens arrive and revive the wife (Vampira), a policeman (big Tor Johnson), and "Bela" (played by chiropractor friend of the director hiding his face with a cape), it's all laughs. Audiences stare in disbelief at the studio floor under the moving grass in the cemetery, flying saucers made of paper plates, night constantly changing to day and back again, and a jet cockpit set that elementary school kids could have designed for a play. TV psychic Criswell narrates ("Can you prove this didn't happen?"). In fact, he says it all: "There comes a time in every man's life when he just can't believe his eyes." Gregory Walcott and Mona McKinnon play the modern couple living near the graveyard. Dudly Manlove (!) plays the effeminate Eros the Alien, aided by Joanna Lee, now a rich TV writer. Lyle Talbot (in his third Wood film) plays a general with a little Washington office. Wood was also in charge of the special effects and editing. Worth watching nine times.
From "Leonard Maltin's Movie and Video Guide":
BOMB. Hailed as the worst film ever made; certainly one of the funniest. Pompous aliens believe they can conquer Earth by resurrecting corpses from a San Fernando Valley cemetery. Lugosi died after two days' shooting in 1956; his remaining scenes were played by a taller, younger man holding a cape over his face! So mesmerizingly awful it actually improves (so to speak) with each viewing. And remember: it's all based on sworn testimony!