Discovery of the archaeological trowel and the crime scene in the tool shed

The discovery of the missing archaeological trowel and the crime scene in the tool shed is the turning point at which Rob Ryan’s investigation of Katy Devlin’s death moves from suspicion to physical evidence. A recollection about an unaccounted-for tool leads him to Sean Callaghan, then to a coordinated search of the Knocknaree dig. The search recovers the trowel hidden beneath tarpaulins; luminol testing in the separate finds shed then reveals blood and establishes that Katy died there. Together, the discoveries connect an everyday object to the crime and expose the investigators’ earlier proximity to its scene.

The missing trowel and Sean Callaghan’s account

Rob’s lead comes to him as he is leaving the archaeological site. He has just watched the tension between Mark Hanly and Macker subside, and the other archaeologists have returned to work. As Rob buttons his coat, he suddenly remembers the trowel: the missing tool may be relevant to the crime. The realization changes his purpose at the dig. Rather than leave, he seeks out Sean Callaghan and asks whether Sean ever found his trowel. Sean says he had to buy another one, and Rob presses him for the last time he remembers having it.

Sean traces the loss to the finds shed. He had found a coin and carried it there on his trowel to show Dr. Hunt, because he understood that handling an old coin could damage it. Dr. Hunt consulted books to identify the find, and Sean left at about half past five without taking the trowel with him. At first, Rob understands Sean to mean that this happened on the Thursday the investigators came to speak with Mark. That timing would make the lead much less useful, and Rob feels his confidence drain away.

Sean corrects the chronology. The coin and the forgotten trowel date from an earlier Monday; the Thursday visit was merely the first time he needed the tool after leaving it behind. In the intervening period, the team had been mattocking a drainage ditch, and Sean assumed someone had picked up the trowel and failed to return it. When he finally needed it, his colleagues denied seeing it. The distinction between the Monday when the trowel vanished and the Thursday when Sean noticed its absence places the loss on the evening Katy Devlin died, giving Rob a reason to reopen the question of where the tool went.

The search of the archaeological site

Rob calls Sam O'Neill from the road, presenting the call casually while he waits for Sam to answer. He asks for Sam, Cassie Maddox, several other investigators, and a team from the National Bureau of Criminal Investigation to come to Knocknaree as quickly as possible. He specifically requests Sophie Miller if available, along with a metal detector and someone able to operate it. Sam agrees and hangs up. Rob’s call turns a private deduction into a large operational commitment.

When the team arrives, Sam has brought Sweeney, O'Gorman, and another investigator; Sophie and her team prepare their equipment, while Cassie is with them. Rob explains why the missing tool matters. Archaeological trowels have a leaf-shaped metal blade attached to a short wooden handle, and Sean’s was marked with his initials, SC. Sean says he left it in the locked finds shed at half past five on Monday evening. Rob notes that the missing trowel matches Dr. Cooper’s description of the implement used in the attack on Katy. Because Sean says he did not know the tool would be left there, Rob considers the possibility that it became a weapon of opportunity, with the finds shed potentially serving as the primary crime scene.

Rob also sets out what remains uncertain. Ian Hunt, Mark Hanly, and Damien Donnelly had keys to the finds shed, though Sean could not be ruled out because he might have invented his account of leaving the trowel there. Hunt and Hanly had cars, so either could have transported or hidden a body in a vehicle; Rob understood that Callaghan and Donnelly did not have cars, which would make a hiding place nearby on the site more likely if either had been involved. These are investigative possibilities, not established conclusions. Rob directs the team to search for the trowel, a bloodstained plastic bag, and both primary and secondary crime scenes.

Recovery beneath the tarpaulins

The search spreads across the site, and Rob waits amid the investigators’ activity, increasingly aware of the scale of the gamble he has taken. He could have asked Sophie to inspect the finds shed without summoning nearly everyone connected to the investigation; instead, he has taken over the site. If the lead proves false, he expects O'Kelly to question the decision. That pressure makes the call to Rob from the tools shed a decisive reversal: Cassie reports that they have found the trowel beneath tarpaulins.

Sam is kneeling at the rear of the tools shed, lifting the tarpaulins beside a broken wheelbarrow. The trowel has been forced down between the pile and the wall, behind the covers. Its point has torn the tough material where it caught. In the dim shed, Sam shines a torch on the handle, revealing SC burned into the varnished wood in large, uneven Gothic letters. The inscription identifies the tool as Sean Callaghan’s, while its concealed position makes the find more than a routine recovery. Sam observes that the tarpaulins were behind other equipment and did not appear to be used often. The investigators also recall Dr. Cooper’s suggestion that Katy had probably been wrapped in something before she was found, making the covers a possible connection worth investigating rather than proof on their own.

Blood evidence in the finds shed

The recovered trowel leads the investigators back to the finds shed, where Sophie uses luminol and a black light to test the floor and the area around the shelves. The procedure makes traces that are not visible under ordinary lighting appear, allowing the team to examine whether blood has been cleaned away. Under the ultraviolet light, the floor shows scattered marks, areas where blood had pooled, and signs of wiping; droplets and a hand-shaped smear are also visible near the lower shelves. Sophie has the site swabbed, and the test confirms that the material is blood.

Rob recognizes the consequence immediately: Katy Devlin died on the floor of the finds shed. The revelation changes the meaning of the room, not merely the status of the trowel. Rob and Cassie Maddox had previously sat there and interviewed the killer, without realizing they were at the crime scene. The discovery therefore establishes a direct forensic fact while also exposing the investigators’ earlier failure to recognize the setting. The event’s significance lies in that double reversal: a tool first remembered as missing is recovered hidden at the dig, and a routine interview location is revealed as the place where Katy was killed.