The Joker is the final villain of the series in I,The Knight. Some say the one called Joker was once just a humble circus clown who went insane and others say he was just born like that. The Joker made his presence known in Gotham when he had his men rob six banks at the same time. While Batman and Oracle dealt with the banks, Joker detonated a bomb in city hall killing everyone in it. The Joker announced during a tv broadcast that it was only a taste of what he was capable of. The Joker then kidnapped Jim Gordon and shot him in the stomach. That was when Batman arived and did battle with Joker. The Joker used a large sledge hammer and his various acrobatic movements to fight Batman. Soon Batman had Joker on the ground and demanded to know why he was doing all of this. Joker simply replied "Because life is just an allusion. Life is cruel,unforgiving and vain. I'm doing everyone in Gotham a favor by killing them. So why don't you just kill me and get it over with? You know you want to heheheheh." Batman replied with "Because i'm not like you." and proceeded to knock Joker unconscious.
He is played by Andy Serkis.