In the story of The Princess Bride, Rugen is Prince Humperdinck's evil sidekick. He's a hulking man who has six fingers on his right hand and was given his title as a birthday present. Though Inigo doesn't figure out who Rugen is until many years later, Rugen brutally murders Domingo, Inigo's father, when Inigo is ten years old. Inigo carries the six-fingered sword that Domingo made for Rugen. In the present, Rugen does whatever he can to support Prince Humperdinck, including scouting for possible brides and affirming whatever he says. After he and Humperdinck catch Westley, Rugen reveals that in addition to being Humperdinck's right-hand man, he's also an academic who's interested in pain. He tells Westley that he's written several scholarly articles on pain and hopes to write a book with what he learns from studying what happens to Westley in the Machine. The Machine is something that Rugen has been working on for ten years; it's a silly-looking device composed of many suction cups and a dial. It is, however, lethal and horrifying—the suction cups suck years of life out of a victim. True to his scientific nature, Rugen is very annoyed when Humperdinck uses the machine to kill Westley, as he will no longer be able to experiment with the different pain levels the machine is capable of delivering. Though he doesn't recognize Inigo at first, Rugen inexplicably runs from him after Inigo breaks into the castle. Rugen begins his fencing match with Inigo in the lead, but Inigo manages to pull ahead and cut out Rugen's heart. Rugen dies of fear before Inigo can finish the job.