Mingo was standing between Archie and Susan, within two yards of the body, but he seemed to make a point of not looking at it. “These aren’t aggressive animals,” he said. “They basically spend their lives alone, in hiding. The only reports of attacks are when they’re stepped on or handled.”

“He’s got a mark on his hand, just like the others,” Robbins said.

Archie’s throat tightened. That made four. Five if you included Henry. And they still knew next to nothing about the killer.

The forensic investigator beside Robbins slipped a plastic bag over the corpse’s hand and used a twist-tie to secure it around his wrist.

“You said you know him?” Anne asked Archie.

Archie unzipped his coat. He was hot. The humidity was getting to him. “He was at the camp last night,” Archie said. “He knew we were looking for someone, knew about the octopus attacks. I warned them. Specifically.” If they couldn’t protect people who knew to be careful, knew what to look for, how would they protect a city full of people who didn’t even know to be afraid?

“So he wouldn’t have picked it up,” Anne said. “He knew not to. But he might take it in his hands before he knew what it was. If it came from someone who didn’t appear to be a threat. Someone he knew. Or someone he had reason to trust. With the exception of Henry, they’ve all been found in the water?”

She didn’t wait for the answer. She knew it. She was just talking it through now. “The killer waits for them to die, then pushes the bodies into the river,” she concluded.

Archie nodded. “He likes to watch.”

“Or she. Women are more likely to use poison.” She wheeled around to Mingo. “What happens to the victims? After the poison hits?”

But Mingo was looking at the body now, his eyes wide behind the fake glasses. Archie had seen it before. Once you looked, you couldn’t look away. The professor’s pallor went from Northwest pale to ash. “The toxin causes respiratory paralysis,” he mumbled.

This was why Archie didn’t like bringing amateurs to crime scenes. Pretty soon Mingo would be in the bushes vomiting, and then they’d have that smell to deal with on top of the decomp.

“No, I mean step by step,” Anne said. She took Mingo’s pointy chin in her leather-gloved hands and gently turned his head. “Look at me. Not him.” She smiled at him. He blinked. Took a breath. Adjusted his cap. His Adam’s apple rose and fell. “There, now,” she said. “You’re okay. Now tell me, this toxin, what does it feel like?”