- "You dirty, little.... f**king prick!"
- ― King's last words to Eggsy before his death.
Chester King, also known by his codename Arthur, was the head of Kingsman from an unknown point in time prior to 1997 until 2014. However, he also was a supporting antagonist in the film Kingsman: The Secret Service because he had betrayed Kingsman and was in league with infamous philanthrope Richmond Valentine he helped in his plot to wipe out most of the human race and establish a new world order.
Chester King was portrayed by famous British actor and producer Michael Caine.
Recruiting for the new Lancelot
Following the death of fellow agent Lancelot, Arthur and the rest of Kingsman personally recruited a candidate of each of their choices to replace him. Arthur's pick was Charlie Hesketh. After Arthur told the other agents to pick their respective candidates, Merlin told him and Harry about how Lancelot was trying to pull off a rescue mission of Professor James Arnold, a university lecturer who had recently been seen at Imperial College (where he worked). Arthur then told Harry to pick a "more suitable candidate" (showing a distain for Harry's previous pick, Lee Unwin), which led to Harry retorting that Arthur was a snob.
Harry later found and tried to interrogate Arnold about his kidnappers, only for Arnold's head to explode and Harry to later end up in a coma. Merlin and Arthur met over Harry, and Merlin told Arthur that Harry hadn't any brain trauma but they weren't sure how long he'll be comatose for, as well as that they weren't able to see his footage. Thankfully, Harry recovered. The chip, meanwhile, was traced back to Richmond Valentine, who was planning on sending out free SIM cards to everyone to offer free internet access.
During Kingsman's test to see how loyal the trainees were to the agency, King had Charlie tied to some train tracks and pretended to be an interrogator that offered to free him in exchange for information about Kingsman and Arthur. Charlie gave up what he knew and King dropped his disguise. He then stated his disdain for Charlie and left him where he was for what he did.
With Eggsy and Roxy - one of the other candidates - left, King tried to get Eggsy to shoot his pet dog JB in order to pass and become the new 'Lancelot'. However, Eggsy refused to kill his dog (being unaware that the gun only hold blanks), resulting him to fail and Roxy to become the new 'Lancelot'.
Betraying His Agency
Unknown to a lot of people, Valentine was actually using the SIM cards to release a neurological wave to cause anyone who had them to become extremely violent. Valentine approached Arthur about this and claimed that he was doing it so as to create a culling by having the people with the SIM cards kill each other in an attempt to deal with the over-population problem. Arthur seemed interested in this and Valentine had an implant inserted into his neck which left a small scar.
Arthur witnessed Harry trying to find Valentine in the crowd of the South Glade Mission Church, thinking he was there, and the massacre which nearly killed everyone while leaving Harry the lone survivor. Arthur then saw him being shot and supposedly killed by Valentine, while looking on in shock. This led Eggsy to return to the Kingsmen headquarters to try and stop Valentine, only for Arthur to claim that Valentine had been handed over to the police after Harry's glasses had apparently recorded Valentine's confession. In memory of Harry, King offered Eggsy a brandy, only for Eggsy to notice Arthur's scar on his neck which tipped him off that Arthur had done something to Eggsy's drink.
Outraged by King's treachery against his very own agency, Eggsy slyly switched the drinks, causing King to poison himself by accident. Arthur then called Eggsy a 'dirty little fucking prick' before finally succumbing to his death by the poison. His position as Arthur would later be taken by Sir Giles following the deaths of Valentine and his forces.
Arthur was presented as a gentleman and most likely come from a rich background. Unfortunately, this made him out to be a snob; he didn't see Lee as a suitable candidate for Kingsman (despite his heroism in saving Harry) and claimed that "he wasn't really one of [them]". He also explicitly stated that he didn't think Eggsy would have got so far as he did in his training, and stated that he knew Eggsy would never become a Kingsman. He might have also have been somewhat of a hypocrite, as he spoke with a Cockney accent in his last moments, which might possibly mean he didn't come from a posh background as much as he made it out so be.
- Richmond Valentine - Enemy, turned Ally