Doctor Augustus P. Crumhorn the fourth is a brilliant billionaire industrialist and the "Daddy" of Princess (Dawn Crumhorn). He is an occasional antagonist of Danger Mouse who's secretly biding his time to, through his companies, rule the world. He is voiced by John Oliver.
Crumhorn is a thin doberman, with the typical black and brown color scheme. He clothes consist of a blue shirt, red belt, black pants, and a pair spectacles.
Crumhorn IV, is an manipulative, cunning, corrupt business man out to claim the world as his own. While initially coming of as calm, nice, and collected, anyone who's met him would say otherwise. He has no qualms with enslaving the entirety of humanity, destroying hospitals for no reasons, and even murdering his allies if it means success.
Though it does appear he has a soft spot for Dawn Crumhorn (The Princess), as he spoils her with whatever she could want and he does seem genuinely fatherly towards her. Even after she inadvertently ruined his scheme in Mousefall, he still wished her the best as she was his daughter. Still though this doesn't mean he won't get upset with her if she throws a fit or becomes to much of a hassle.
While he is an egoist, he's fairly secretive about his agenda. Unlike someone like Greenback, who's fairly open about being evil, Crumhorn prefers to work from the shadows, hence why he didn't appear until the Season finale. He even got upset with Ian and called him an idiot when he put the Crumhorn label on literally everything in the world, as he doesn't want anyone to know what he's scheming until it's to late for his victims.
- Mouse Rise
- Dark Side of the Mouse
- It's implied that, similar to how agent 58 is the son of agent 57, that Doctor Augustus P. Crumhorn IV is the son of Doctor Augustus P. Crumhorn III
- He the second villain with a daughter who also happens to be a villain, the first being Greenback.
- Though Crumhorn's daughter was introduced before Greenback's daughter, Crumhorn himself wasn't reveled to be a villain til after both Greenback's and Delilah's debut.
- He claims in MouseFall that he created Giraffe Warriors, thought the ancient witch The Queen of Weevils claims that Giraffe Warriors have been around since her youth in her debut "Queen of Weevils" (episode).