He was portrayed by Tobin Bell who also portrayed Jigsaw in Saw.
Peter Kingsley was involved with Max and Alexander Trepkos in the plan to start a war and raise the oil prices. He was also involved with the Second Wave terrorist group, led by Syed Ali, and involved Roger Stanton and Sherry Palmer in his plan.
The first phase of his plan was for Syed Ali to detonate a nuclear bomb in Los Angeles. Stanton had an elite paramilitary unit called Coral Snake, as he intended for them to intercept the bomb, as Kingsley promised no casualties. However, Kingsley fully intended the bomb to go off, and had one of his men in Coral Snake, Jonathan Wallace, kill his teammates.
The bomb was discovered and taken to the desert by George Mason, and only he was killed in the explosion. Although Los Angeles was not destroyed, they became aware of the bomb all the same. The next phase of Kingsley's plan was for a tape to be found in Syed Ali's house, which had the voices of three leaders of Middle-Eastern countries discussing the plot. This tape was forged by Kingsley, so that the US would launch a retaliatory strike against these countries and start the war.
Jack Bauer found a chip containing evidence of the forged tape, however, Kingsley's men, led by Ronnie Stark, captured and tortured him. When Stark nearly killed Jack by causing his heart to stop, Kingsley had another of his men, Raymond O'Hara, kill Stark and replace him, although he and the other mercenaries were killed by Jack soon after as he escaped. However, during a fight with a mugger, the chip was damaged.
Alex Hewitt, the computer expert Kingsley hired to forge the tape, was targeted by Kingsley, who wanted him killed in the explosion. Jack got to him first and tried to take him to CTU and get him to give the evidence that the tape was fake. However, he attempted to escape from Jack, who was forced to fight back, accidentally killing him.
This left only one option. As Kingsley did not know Hewitt was dead, Jack got Sherry to talk with Kingsley about making a deal to turn Hewitt over to him. While wearing a wire, she got him to confess that he forged the tape. He became suspicious of Sherry shortly after and ordered his sniper to shoot her, but the sniper, Scott, had already been killed by Jack. Jack killed the last of Kingsley's bodyguards, but ran out of ammo and was cornered by Kingsley. Before Kingsley could shoot Jack, he was shot by a CTU sniper from a helicopter.