Broadway producer Peter Duluth sought solace in a bottle after his wife's death; now, two years later and desperate to dry out, he enters a sanitarium, hoping to break his dependence on drink - but the institution doesn't quite offer the rest and relaxation he expected. Strange, malevolent occurrences plague the hospital. Among other inexplicable events, Peter hears his own voice with an ominous warning: "There will be a murder." It soon becomes clear that homicidal maniac is on the loose and, with a staff every bit as erratic as its idiosyncratic patients, it seems everyone is a suspect - even Duluth's new romantic interest, Iris Pattison. Charged by the baffled head of the ward with solving the crimes, it's up to Peter to clear her name before the killer strikes again.