The Midnight Warning on AllMovie

Inspired, it was stated at the time, by a real event, this minor but well-made Poverty Row mystery features Claudia Dell as Enid Van Buren, a young girl who checks into Apartment A at the Clarendon Arms Hotel with her brother, Ralph, and fiancée Erich (John Harron). But Ralph mysteriously disappears and to Enid and Erich's bafflement, no one at the hotel seems to remember his presence. Enter noted investigator William Cornish (William "Stage" Boyd), who, for one, takes the girl seriously and promises to help. But neither Cornish nor his personal Dr. Watson, Dr. Steven Walcott (Hooper Atchley), can prevent someone from luring Enid to a nearby mortuary where corpses suddenly seem to come to life. As it turns out, the owners of both hotel and mortuary are covering up a deathly secret, a secret that would mean their ruination should it become public.