When an eccentric uncle wills a huge, ramshackle house to Cyrus and his impoverished family, they get the shock of a lifetime. Their new house comes complete with a spooky housekeeper, Elaine, plus a fortune in buried treasure and 12 horrifying ghosts. As the terrified family soon discovers, these haunted ectoplasms include a decapitated man, a wailing lady and a flaming skeleton, who are held captive in the eerie house and must find an unlucky 13th to free them.