MJ is described as the “sidekick of the star” Wally Cardew, a popular YouTuber who once voiced Drek in The Ink Black Heart cartoon. When Strike first looks at Wally’s YouTube channel after talking to Madeline’s son, he notices that most of Wally’s videos are headlined “The Wally Shows MJ Show.”

MJ is initially described as a “cheery-looking, chubby-faced, bearded, brown-skinned young man” (Ch 13). In a livestream that Strike watches at Madeline’s, MJ has neater hair and has lost weight since the 2012 video Strike had watched before.

In the first YouTube video Strike watches of the duo, titled “The Ink Black Fart,” Wally makes a joke about MJ not understanding legals, to which MJ replies that his uncle is a lawyer. In the livestream Strike watches later that night, Wally announces that twenty-five percent of all merch purchased will be donated to Great Ormond Street Hospital, because MJ’s little cousin is being treated for leukaemia there.

MJ participated in the infamous “Cookies” video with Wally in March 2012, in which they made jokes about the Holocaust. The video led to Wally getting sacked as Drek in The Ink Black Heart, despite Josh’s wishes that he stay –- it was Edie who wanted him gone.

When Dev Shah is conducting surveillance on Wally’s flat, he hears shouting from inside before MJ storms out looking like he’d been in a physical fight. Robin takes over surveillance from Dev and, a couple of hours later, Wally emerges from the flat talking on the phone. Six men, who Robin thinks could be relatives of MJ, jump Wally and beat him up. Wally is taken to hospital in bad condition. Robin notices that Anomie is active in the game while Wally is lying on the floor, so they rule him out as a suspect.