All these while and all he should have done was to interrogate Isleen. Liam's brother who died during the attack was also somehow connected to Isleen indirectly too.
The dead teacher did too. Now, a woman in her street. He hoped to hell that this victim had never in any way interacted with Isleen.
If she had, it meant something was linking Isleen to some of these deaths. Perhaps, they had more than one killer. Maybe one was connected to Isleen in some way and the other, the random killer.
He knew good people when he saw them, so he knew Isleen was one. If not too good for her own good. But something was connecting some of these killings to her and he better find out what or who before someone else cracked it and it got her in trouble.
People like Principal Thorne would get her in trouble. For her, he needed to solve this case and save her from whatever impending danger. He had no idea why but he could sense it– almost feel it.