But most exciting of all was the link that Zoe had been waiting for. His plain shirt had been ripped open, traces of blood still clinging to it where it had been thrown aside. Across his bare torso, another equation was written in thick black numbers and letters.
The blood was still wet. He had been killed in the last hour or less. Even as they watched, a small piece of brain matter that had attached itself to the wall slowly peeled away and dropped down. This crime scene was still settling into place.
This had happened while they were at James Wardenford’s home, arresting him, or at least in the minutes before or after. No way he could have got home, washed himself off, and played the part of the drunkard in time. Even the first part would have been too much of a stretch, given the distance between the homes. Wardenford was in the clear.
Shelley was taking it all in, breathing through her mouth rather than her nose, and Zoe took that as her cue. She was long used to gruesome scenes like these, and it was all just meat to her. Better that she take the lead while Shelley found her feet.
“What was his schedule for today?” Zoe asked.
The policeman flipped back a page in his notebook. “He finished his last shift early this morning, and then was due back in this evening at nine to handle a late shift. Looks like he was getting some shut-eye beforehand.”
Shelley had recovered enough to draw closer to the body. “Any initial forensics reports?”
The officer followed her, leaning in to point at various parts of the skull with an outstretched pen. “They tell me the doctor was stunned first with a single blow, here. We can only just see the edge of the impact mark under all the rest of it, but it was likely solidly across the front of his head. Enough that even if he woke up, he’d have been out of it. Difficult for him to fight back at all.”
Shelley nodded, while Zoe ranged around the room, careful where she stepped. She was making calculations. She knew it took around a thousand pounds of force to cause the average skull fracture. Their killer certainly was not heavy or strong enough to provide that force himself—so he must have used something heavy, and thrown it down on top of the victim’s head.
“Have you recovered the weapon?” she asked.
Their guide, as well as the three forensics officials still working in the room, all shook their heads.
“Heavy, but thin,” Shelley suggested, studying the impact marks on the man’s face.
Zoe nodded approvingly. “No wider than my hand. Dropped three or four times, with decreasing force each time. Our killer was running out of strength.”
“Then, did he bring it with him? Or take it from the house?”
Zoe thought that over. “Interesting question. Either he planned in advance very carefully, or he took an opportunity when he found one. What do we think?”
“He seems like both. It’s a paradox, this case. Planned and premeditated—he waited for the professor. Took the student somewhere that wasn’t covered by surveillance. But the killings themselves are rage-driven, spontaneous. Using the environment.”
“How did he get in?” Zoe directed her question at the officer.
“Back door had been sabotaged. It’s almost as old as the house, beautiful wood paneling. Someone carefully and slowly sawed through it, put their hand through one of the panels, and turned the key from the outside to let themselves in. The doctor had ambient noise playing in here over his smart speakers. He wouldn’t have heard a thing, I don’t think.”
Zoe was done with the scene; she knew everything she needed to, from there at least. Nothing contradicted her earlier thoughts that the killer would be five foot nine, of average build, but perhaps a little muscular. Now she could let herself indulge in the one thing she was really interested in.
She took out her phone and started taking photographs of the equation, angling herself in to get the best shots. Shelley and the others in the room continued low conversations, but Zoe tuned them out, only keeping herself vaguely aware of what they were saying in case something important came up.
The shots taken, Zoe drifted down out of the room and down the corridor, lightly nudging the next door open with her elbow so as to avoid touching the handle. There was light afternoon sun streaming through the large windows, illuminating a miniature gym room with a treadmill set up to face the view.
Zoe moved past it, examining the other items. A large blue balance ball, several straps and lengths of stretchy material used for strength training. A rowing machine, low on the ground, with an empty water bottle still fitted into the appropriate slot.