The film opens in Victorian era London on a December night in 1900. The first night of the season at the Royal Opera House finds the opening of a new opera by Lord Ambrose D'Arcy (Michael Gough), a wealthy and pompous man, who is annoyed and scornful when the opera manager Lattimer (Thorley Walters) informs him the theatre has not been completely sold out. No one will sit in a certain box because it is haunted. Backstage, despite the soothing efforts of the opera's producer, Harry Hunter (Edward de Souza), everyone, including the show's star, Maria, is nervous and upset as if a sinister force was at work. The climax comes during Maria's first aria, when a side of the scenery rips apart to reveal the body of a hanged stage hand. In a panic, the curtain is rung down, and Maria refuses to sing again.