His Mystery Girl is a 1923 American silent comedy film directed by Robert F. Hill and starring Herbert Rawlinson, Ruth Dwyer, and Margaret Campbell.

[1][2] As described in a film magazine,[3] the friends of Kerry Reynolds (Rawlinson) think he should be a more human young man and scare him into going to his doctor.

Leaving the doctor's office he sees a beautiful young woman apparently in distress and she wins his heart.

Kerry gets a message that she is a prisoner in a deserted house, and after some adventures he arrives to save her, and gets into a tremendous fight with a band of men who might be her kidnappers.

Finally, when he takes her from her home to the Justice of Police where he hopes to marry her, his friends tumble out and tell him that it has been a great practical joke on their part, and that the young woman is a student from a drama they hired to lead him into some adventures, and that the main villain is her brother.