The Monster is a 1925 American silent horror comedy film directed by Roland West, based on the stage play of the same name by Crane Wilbur, and starring Lon Chaney and comedian Johnny Arthur. The screenplay was written by Willard Mack and Albert Kenyon. It is remembered as an early prototype "old dark house" movie, as well as a precedent to a number of horror film subgenres such as mad scientists with imbecilic assistants. Some sources list the film's release date as March 1925, while others say February.

The film has been shown on TCM network with an alternative and uncredited musical score. West later went on to direct The Bat (1926) and its later sound remake The Bat Whispers (1930).

Although the film only earned $55,600 for the week ending on February 18, 1925, the film could be considered the first horror film in history to top the North American box office because the gross reported by Variety was the highest amount listed for that week in theaters nationwide. The movie was made by Roland West Productions and Tec-Art and distributed by MGM. The film was released with lavish color tints that enhanced the eerie mood.

The film's tagline was "A mystery thriller and a love adventure. The romance of a boy and a girl in a mansion of hidden motives. You'll Guess! You'll Gasp! You'll love it! A Mansion of Many Doors- A House of Strange Shadows - What lies beyond the door? WHAT does it mean? Who can solve it? You'll keep guessing until the very end."