He had two different hair colors, the majority blonde, and his sideburns brown. Above the temples, two strands of blonde hair reach down, right above the eyes. He had no visible eyebrows so he had a large, jutting forehead. His nose is large, and pointed. His eyes have a somewhat pale yellow tint, and had dark circles under his eyes. He wore a large, black trench coat, with a orange undercoat. He also wore brown, baggy pants, with brown shoes.
One day, Makepeace murdered someone out at a street. Justin Lawson found out that Makepeace was the murderer; instead of turning Makepeace in, however, Lawson told him to kill on orders. Makepeace was thus ordered to kill at least 14 people, with 11 other victims connected to him by Lawson simply putting a puzzle piece at the crime scene. On one occasion Keelan took his daughter to one of his killings and took a picture of them as memorabilia. Makepeace's targets were always people he didn't know, except for one case where he murdered the millionaire he owed money to.
Makepeace remained at large for a period of time due to Lawson's rank in the police force; if another member of the force ever got close to solving one of the murders, Lawson would destroy vital evidence. His daughter Diane noted to Lucy Baker that Makepeace was able to evade capture for his personal murder despite Alfendi's investigation, because someone had taken away vital pieces of evidence that would have implicated Makepeace. Although that someone was Lawson, it was clear that Makepeace had never discussed this with anyone; Diane had mistakenly believed that it was Alfendi because he was the one who did the case files.
Eventually, though, the investigation led to Forbodium Castle where Makepeace was hiding, and the murderer was confronted by Inspector Alfendi Layton who had gone on ahead to arrest Makepeace while New Scotland Yard was preparing to move out. After a chase up to the west tower of the castle, Makepeace shot Alfendi in the chest causing Alfendi to pass out and collapse. He acted as if he had been shot in his right side just as Hilda Pertinax and Lawson arrived after hearing the gunshot, making it look like Alfendi had shot him. Lawson arrived and as part of the hoax, shouted out for Alfendi to put down his gun; this was how Lawson was able to mislead Hilda and implicate Alfendi for Makepeace's murder.
Following the charade, Lawson then crossed over the ledge to the other tower using the vines that grew along the central tower. Lawson then shot Makepeace once in the left side, then in his head, ending his connection with the Jigsaw Puzzle Killings and pinning Makepeace's death on Alfendi.
Four years later, Lawson used the same trick to kill Diane and implicate Alfendi once again, but Lucy Baker was able to figure out Lawson's modus operanti by connecting the mystery of both murders to the broken ivy.
His name's pronunciation makes the phrase "kill and make peace". It is possibly referencing that some of the people he killed were evil, and killing them would stop trouble, therefore, killing, to make peace.