Jones's staged Walsingham Gallery graffiti incident begins as an accusation on a window and ends as part of a calculated attempt to divert suspicion, implicate Rupert Darby, and buy time while Peter Diamond closes in on Gilbert Jones. The message that Shirley-Ann Miller saw was not a reliable clue to Sid’s killer: Jones later disclosed that it was false, and that the graffiti had been staged as part of a broader plan.

The message and its discovery

The graffiti appeared on the Walsingham Gallery window on the evening of a party. Its words, “She did for Sid,” invited readers to blame a woman for Sid’s death. Shirley-Ann Miller later told the police she had seen the writing herself. Jessica Shaw had practically dragged her into the street to look, and Shirley-Ann insisted on the value of what she had seen: these were facts, not intuition. That distinction gave the message a witness, but did not make its accusation true.

The writing had not attracted notice from the party guests at first. Barnaby Shaw explained that the gallery lights made it inconspicuous: people tended to look through the windows rather than at them, and nobody had remarked on it until he and Jessica noticed it themselves. Jessica was upset, but Barnaby, A.J. Smith, and Shirley-Ann Miller persuaded her that it was not serious and better ignored. Barnaby wiped the writing away instead of reporting it. The combination of an initially overlooked message, its removal, and the absence of a report helped keep the incident from being treated as an obvious public warning.

Conflicting accounts and the cover-up

When Peter Diamond asked Barnaby about the writing, Barnaby was rattled and wanted to know who had told the detective. He said that Jessica had no idea who was responsible, and that she was upset by the graffiti. His account also placed the decision to dismiss the matter with a group: A.J. and Barnaby, together with Shirley-Ann Miller. Jessica had brought Shirley-Ann out from the party to see the message, apparently choosing the first member of the Bloodhounds she could reach.

This recollection sits alongside Shirley-Ann’s account of being taken outside to see the words. Her testimony establishes that she saw the writing; Barnaby’s account explains how it was then treated and removed. Much later, he acknowledged that Shirley-Ann had admitted covering for A.J. She had worked out that A.J. was responsible, though Barnaby did not think A.J. had told her. As events unravelled, a new plan was devised to frame Rupert Darby and fake his suicide. The episode therefore involves more than the original concealment: knowledge of A.J.’s role and the choice to protect him become part of the later conspiracy.

Jones’s purpose and the intended frame

Gilbert Jones eventually explained why he arranged the gallery message. Peter Diamond had been closing in, and Jones feared that he would be investigated unless something dramatic distracted the police. He first considered Jessica Shaw, whom he regarded as clever enough to have written the riddles and whose party at the gallery would give a message on the window an audience. His stated purpose was to attract attention and create a distraction, buying time while suspicion moved elsewhere.

The distraction also needed a person to blame for writing the graffiti. Jones chose Rupert Darby precisely because Darby was a stranger to him and had not crossed his path. Jones made sure Darby was conspicuously marked with spray paint; the beret made him easy to recognize. In Jones’s account, this made Darby a better target than Jessica. The sequence transformed a message intended to misdirect attention into preparation for a much graver false accusation: Rupert would appear to be responsible for the graffiti and, if his death were staged as suicide, could be made to seem guilty in a wider sense as well.

Reversal and significance

The message’s most pointed claim was also its decisive deception. Asked why the conspirators would draw attention to their guilt, Peter Diamond was told that the accusation was untrue: Shirley-Ann had not killed Sid; A.J. had. Jones’s explanation recasts “She did for Sid” from a revelation into a planted misdirection, one designed to point toward a woman while concealing the man responsible. Its apparent simplicity—an accusation written where party guests might see it—concealed a layered strategy of attention, removal, cover, and eventual framing.

The incident also changes meaning as the investigation advances. At first, it is a troubling message that Jessica finds upsetting and Barnaby dismisses as insignificant. Shirley-Ann’s insistence that she personally saw it gives Diamond a concrete lead. Barnaby’s admission identifies the people who chose to wipe it away, while Jones’s confession links the staged writing and Rupert’s conspicuous paint marks to his effort to divert the investigation. What was erased from the glass thus persisted as evidence in the chain of events: not proof that the words were true, but evidence that the apparent accusation had been engineered to mislead.