Jonathan Devlin’s police interrogation brings the investigation’s competing strands—Sandra Scully’s rape, the disappearance of children from Knocknaree, and Katy Devlin’s death—into one room. Jonathan provides a limited admission about his movements in 1984, but no confession or charge follows. The interview’s decisive turn is less a conclusive answer than the investigators’ conviction that he is withholding something, a certainty that culminates in Rob Ryan abandoning professional restraint and Cassie Maddox having to intervene.

Witness Leads and the Interview’s Opening

Before questioning Jonathan, the detectives had been trying to establish what Jessica Devlin knew about a man who had spoken to Katy. Jessica had first said that the man frightened Katy, then withdrawn into silence when asked to explain. When the detectives later sought her account directly, Rosalind Devlin began to supply what Jessica had told her. Rob stopped her: Jessica herself needed to speak, because Rosalind’s account would be hearsay and inadmissible in court. The distinction matters in the later interview: suspicion and family accounts may direct questioning, but they do not by themselves establish what happened.

With Rosalind prompting her, Jessica eventually said that she had seen a man talk to Katy on the road as they returned from the shop. Asked when this had happened, she corrected Rob’s phrasing: Katy had not gone away; Katy had been killed. The exchange established a possible lead, not an identification. Jessica did not provide the man’s name or a date, and her attention soon drifted away again. Her uncertain testimony forms part of the case’s background, but it does not itself connect Jonathan to the stranger.

The detectives brought Jonathan into an interview room and formally cautioned him. Rob clarified that the caution was routine and that Jonathan was not under arrest; they wanted an update and his help. Jonathan’s sharp question about whether he was being arrested, and his attention to the wall of photographs, made the exchange tense from the outset. The interview then moved from the rape of Sandra Scully to Jonathan’s account of events in 1984 and, finally, to Katy’s illness and death.

The 1984 Account and the Missing Children

Cassie began by asking when Sandra Scully had been raped. Jonathan placed it in the summer of 1984, without recalling a specific date. Rob told him that the statute of limitations applied, although the detectives had not checked the point; in any case, they had no prospect of charging him for that rape. The assurance kept the questioning focused on what Jonathan might disclose rather than presenting the old case as a charge they could bring.

Cassie challenged his account of being in Stillorgan. She proposed that a cinema visit could have provided an alibi, and argued that the number of assailants mattered to how the three children could have been subdued. Rob offered Jonathan a distinction between being a murderer and being an accessory, invoking Cathal Mills’s claim that Jonathan would not have devised the plan. These were investigative theories and pressure points, not facts established by the interview.

Jonathan then conceded that he had gone to Stillorgan with Cathal Mills and Shane to see a film. He maintained that this was what he had told police at the time. The admission confirmed that he had been with the other two men in Stillorgan, but did not establish that he had participated in the children’s disappearance or that the cinema visit was an alibi. When challenged, he denied that any of them had touched the children, said he knew nothing about what had happened to them, and insisted that he wanted to know who had killed Katy. The case’s central uncertainty therefore remained: Jonathan’s account placed him alongside men implicated in the old investigation, but his own words neither resolved his role nor supplied an explanation for the missing children.

Katy’s Illness and the Detectives’ Suspicion

Cassie shifted the interview to Katy’s medical history. She described four years of unexplained gastric illness, ending in the spring after Katy received another chance at ballet school, and noted that the medical examiner had found no sign of disease. Cassie interpreted the pattern as evidence that someone had poisoned Katy, suggesting substances that could produce illness and emphasizing that a person with daily access to Katy could have harmed her without attracting suspicion. She further proposed that Katy had stopped taking something and might have threatened to tell. These were Cassie’s deductions from the records and timing, not a confession by Jonathan or a conclusion proven in the room.

Jonathan’s visible reaction strengthened the detectives’ suspicion: the flush left his face, and Rob read his pallor as evidence that he knew something. The interrogation thus distinguishes between proof and conviction. The medical history gave Cassie a reasoned theory about prolonged poisoning, while Jonathan’s response appeared significant to the detectives; neither, on its own, demonstrated that Jonathan had poisoned Katy or knew who had. The unresolved gap between what they believed and what they could establish sharpened Rob’s frustration.

Loss of Control and Release Without Charge

Rob’s anger broke through during the questioning. He knew the evidence would not hold Jonathan and believed that Jonathan might leave without facing consequences, yet felt certain of his guilt. Rob lunged at him. Cassie intervened and restrained him, turning what had often been a rehearsed pressure tactic between the detectives into a real struggle. Rob’s own account emphasizes that this occasion was different: he was no longer performing a controlled feint to unsettle a suspect, but acting on his desire to attack Jonathan. The moment exposes the danger in treating intimidation as a routine investigative instrument, especially when personal certainty outruns admissible proof.

After separating them, Cassie resumed the interview with professional composure. She told Jonathan that he would be released without charge for the time being, advised him to remain somewhere the police could find him, and warned him not to contact Sandra Scully. Jonathan accepted the terms and left. His release did not clear him of suspicion, but it made the practical limit of the interrogation unmistakable: the detectives had drawn a connection between the old rape, the missing children, and Katy’s case, yet had not secured evidence sufficient to arrest him. Rob was left to confront not only the failure to obtain an answer but also his own breach of control, and to wonder whether his state of mind was deteriorating.