Sean Callaghan

Sean Callaghan is an archaeological worker at the Knocknaree dig whose missing, personally marked trowel becomes an important clue in the investigation of Katy Devlin’s death. His explanation traces the tool to the finds shed and helps direct investigators toward a possible crime scene, but the evidence presented does not establish that he took part in the crime.

Identity and Work at the Dig

Sean works at the excavation, where he and the other workers handle finds and carry out physical tasks, including clearing a drainage ditch. When the investigator approaches him, Sean is perched on the hood of a Land Rover, eating a doughnut and speaking sociably. The ordinary informality of the encounter contrasts with the importance of the question: investigators need to know where a missing archaeological tool went.

The Missing Trowel

Sean explains that he had taken a coin to the finds shed to show Dr. Ian Hunt. He carried the coin on his trowel because handling old coins with bare hands could damage them. He and Dr. Hunt became absorbed in identifying the find; when the workday ended at half past five, Sean left the trowel on a table in the shed. He says he returned for it the next morning and found it gone.

The trowel was identifiable as Sean’s because he had burned his initials into its wooden handle. He describes doing this with a Swiss Army knife: he heated its corkscrew with a lighter during a spell of heavy rain when the workers had to stay indoors. That distinctive mark makes the missing tool more than an interchangeable piece of equipment; if someone had seen it, they could recognize it as his.

Sean says he did not immediately realize the trowel was missing. While the crew worked on the drainage ditch, he had no need for it and assumed someone had picked it up and would return it. When he next needed it, on the day investigators came to question Mark Hanly, the others denied having seen it. Sean says he had accused Macker of taking it because Macker sometimes did foolish things, but he had thought the disappearance was a prank rather than a theft: the initials made the tool too easy to identify.

Significance to the Investigation

The investigator tests Sean’s account against the timing of Mark Hanly’s questioning and the discovery of Katy’s body. Sean’s first explanation seems to put the trowel’s disappearance at a different point than the investigators’ developing timeline, briefly disappointing the investigator. Sean then clarifies that the tool had been missing for some time before the day Mark was brought in. His recollection restores the possibility that it had been taken earlier than the investigator initially thought.

Investigators connect the missing trowel to Dr. Cooper’s description of an implement used in the assault on Katy. Because Sean says he left it in the finds shed, and because the tool was not expected to be there, the investigator considers it a possible weapon of opportunity and the shed a possible primary crime scene. The search is widened to include the shed, the missing trowel, a bloodstained plastic bag, and possible primary and secondary crime scenes. The investigators also note that several people had keys to the shed and that Sean could not yet be ruled out, while distinguishing that uncertainty from proof of his involvement.

Limits of What Is Established

The tool’s later discovery in the tools shed gives the missing trowel renewed importance when Damien Donnelly is questioned. The investigator uses that discovery to challenge Damien’s account of Katy’s death and press him about what he has omitted. Sean’s role in the evidence remains narrower: he provides the history and identifying detail of the tool, while the available account does not show how it moved from the finds shed to the tools shed or establish Sean’s knowledge of its use. His recollection advances the investigation by making a previously missing object traceable, even as responsibility remains a separate question.