Count Hellford tells to his daughter Irena and her friends Tom, Jimmy and Frank the tale of the blue room, in which three people lost their lives through mysterious causes. Tom wants to win Irena's admiration, and he proposes that each of them takes a turn at spending a night in the room. Tom spends the first night in the room. In the morning everyone discovers to their horror that the room's window is open and Tom has disappeared without a trace.