The forerunner of all serials, What Happened to Mary was a series of twelve monthly one reel episodes, each a complete entity in itself, revolving its immediate dramatic and melodramatic problems within the framework of a single episode and designed more for story and suspense situations than action.

• McClure Publishing Co.
• Edison Studios
• Mary Fuller
• Marc McDermott
• Charles Ogle
• Barry O'Moore
• Bliss Milford
• Bigelow Cooper
• William Wadsworth
• Miriam Nesbitt