Doctor Genius is an incompetent wannabe super-villain, sarcastically referred to as "the greatest criminal mind ever".
In his first appearance, the dog told his story from his own perspective, wearing a Hawaiian shirt with seaside scenery behind him as he did so (later revealed to be a poster on the wall of his jail cell). He told the tale of how he turned to crime, fuelled by jealousy and hatred for heroes such as Sonic and Tails. Using his own scientific prowess, he built a force field vest that generated a barrier around him, making him literally untouchable. Tails attempted to apprehend him but was repelled by Genius' force field. A bank security guard then attempted to shoot the mad scientist only for his shots to ricochet off the barrier. Dr. Genius' invention also turned out to be his undoing because he couldn't grab any cash from the bank vault whilst his force field was active. As soon as he turned it off, Tails brought him down.
He has since reappeared in Sonic the Comic Online, now leading the League of Super-Evil Villains in the absence of Grand Chief Whip. Enraged at Captain Blue and his vigilante group S.P.E.A.R., Genius hired an assassin, Fockewulf De Shrike, to assist the league in wiping out their target, Blue's superior, Mr Gold and the Freedom Fighters.
When this failed, Genius and the other League members went on the run from Blue's men. Wallis and himself were cornered in Metropolis University, where they took hostages, including the Dean. To defend against the lawmen, Genius gained access to some EggRobo Badniks and fitted them with vests similar to the one he used in his first adventure. Unfortunately, these went much the same way, with the Badniks firing on the Freedom Fighters whilst still protected by the shield. The shots rebounded on the inside of the bubble and destroyed each of the EggRobos. Genius and Wallis were promptly arrested (although not before Genius was able to completely bore the Dean) and sent to Metropolis City High Security Prison. Inside, Genius vowed to think of a way to escape whilst sleeping, but his dreams were cut short by the appearance of Gold, who offered the traitors a second chance.