Doctor von Saulsbourg
Doctor Ludwig von Saulsbourg is the main antagonist of the 1922 silent comedy, Doctor Jack. He was played by Eric Mayne.

Sent to care for the Sick-Little-Well-Girl for nearly her whole life, Doctor Saulsbourg's yearly fee for her care was described as sounding like the German War debt. During his care for her, he forbade her from being exposed to sunlight, being near flowers, or hearing singing. He would always keep her in blankets and give her medicine.

The only person who ever held suspicion of him was the family lawyer, Jamison. When Jamison is called to check on his mother by Doctor Jack and seeing her full of energy, Jamison realizes that Jack uses common sense to heal people and hires him to try and heal the SLWG.

When Doctor Jack accidentally kisses the SLWG, von Saulsbourg demands Jack's removal. Jack is able to stay the night when its heard that a madman named Lumpy Logan had escaped. The SLWG becomes full of energy over the excitement and Jack realizes that the SLWG's condition occurred because she never knew excitement. Doctor Jack tries to explain the situation to the SLWG's father, but von Saulsbourg threatens to leave if Jack does not. The SLWG's father dismisses Jack. Determined to heal the SLWG, Jack dresses up like Lumpy Logan and rampages through the house with the SLWG in pursuit.

The SLWG soon learns of Jack's plot and dresses up as Logan herself and begins having fun. The SLWG's father becomes delighted to see his daughter well and finally sees von Saulsbourg for the con artist he was and dismisses him. As Saulsbourg argues with Jack for exposing him, Jack sets the SLWG's dog on him. The dog attacks Saulsbourg forcing him to flee.