The Crimson Stain Mystery is a 1916 American horror film serial directed by T. Hayes Hunter.

[2] In this serial, Dr. Burton Montrose, a scientist, has developed a formula which he believes will make ordinary people into geniuses.

The resulting band of thieves and murderers is led by the fiendish Pierre La Rue, known as the Crimson Stain for his luminous, red-rimmed eyes.

They are pursued by Harold Stanley, editor of the Examiner newspaper, who has vowed vengeance for his father's murder.

Aiding Stanley are his friend, Robert Clayton, his sweetheart, Dr. Montrose's daughter Florence, and a detective, Layton Parrish.