The dream is unusually vivid: Bank employee Vince Grayson finds himself murdering a man in a sinister octagonal-shaped room lined with mirrors while a mysterious woman breaks into a safe. It is so vivid that Vince suspects it may have really happened. To get the dream off his mind, he goes on a picnic with some relatives. When a thunderstorm forces his party into a nearby mansion, Vince discovers that the bizarre room does exist, and it means nothing but trouble.
| Actor | Role |
|---|---|
 Paul KellyCliff Herlihy | Cliff Herlihy |
 DeForest KelleyVince Grayson | Vince Grayson |
 Ann DoranLil Herlihy | Lil Herlihy |
 Kay ScottBetty Winters | Betty Winters |
 Charles VictorCaptain Warner | Captain Warner |
 Robert Emmett KeaneLewis Belknap, aka Harry Byrd | Lewis Belknap, aka Harry Byrd |
 Jeff YorkDeputy Torrence (as Jeff Yorke) | Deputy Torrence (as Jeff Yorke) |
 Gladys BlakeBank Clerk (uncredited) | Bank Clerk (uncredited) |
 Julia FayeRental Home Owner (uncredited) | Rental Home Owner (uncredited) |
 John HarmonClyde Bilyou (uncredited) | Clyde Bilyou (uncredited) |
 Richard KeeneMr. Kern (uncredited) | Mr. Kern (uncredited) |
 Janet WarrenMrs. Dorothy Belknap (uncredited) | Mrs. Dorothy Belknap (uncredited) |
 Stuart HolmesMan with Packages in Elevator (uncredited) | Man with Packages in Elevator (uncredited) |