“I’ll be back for you, Granddad,” he vowed. “But first I have to save Dad and recover those weapons.”

He rose again and surveyed the old lab, aware that Sierra was waiting for him to decide how to proceed. The rush he had experienced a short time ago when he defeated the abyss was fading fast. The overpowering need to keep moving was back in full force.

“We need to find the other tuning crystal, the one that was made for Crocker Rancourt,” he said. “It’s got to be here. It’s the only explanation that fits. With luck it will still be live.”

Sierra walked slowly down an aisle formed by two long stainless steel workbenches. She looked across the room and saw the door of a vault.

“Maybe it’s in there,” she suggested.

North went to the door of the vault, prepared to pull out his lockpick. But when he tugged on the handle the heavy steel door swung open on rusty hinges.

The interior of the vault was lined with glass and steel shelving. There were no artifacts.

“Empty,” he said. “Looks like Rancourt managed to grab all the prototype weapons. That’s probably what triggered the final confrontation. Give me a minute to see if I can figure out exactly what went down in here.”

Sierra stopped at the far end of the two workbenches and looked back at him. “You can work out what happened at the scene of the crime?”

“It’s what I do as a cleaner. No one except you and me has been in here since my grandfather sealed the entrance. I should be able to read the psychic prints.”

He went back to the door of the chamber and heightened his senses. Immediately old footprints began to glow on the floor of the chamber. He sorted through them, separating Griffin Chastain’s tracks from those of the other person who had entered the room.

Even after so many years both sets of prints still seethed with violence, rage and panic.

“It went down hard and fast,” North said. “The killer was standing where I am now when he fired the gun. I can see the heat of his excitement. He’s about to get exactly what he wants but he’s taking a terrible risk and he knows it. He’s nervous. That energy changes at the entrance.”

“Meaning?” Sierra asked.

North concentrated, trying to piece together the story told by the hot prints.

“The killer wasn’t able to get more than a few steps into the chamber after pulling the trigger,” North said. “He’s shocked. There’s a lot of rage and frustration out here in this hallway. He realizes he’s not going to get what he wants after all. He panics and runs.”

“Your grandfather must have generated the abyss and sealed the doorway even as he was dying.”

“Yes.”

“To protect the second tuning crystal?” Sierra asked.

“As far as I can tell, there is nothing else left in here to protect.” North walked slowly through the laboratory, opening doors and closets. He stopped in front of the vault and contemplated the empty shelves inside. “Rancourt had already stolen the weapons and, probably, the tuning crystal he thought was his. Later he must have realized he had grabbed Griffin’s crystal instead. He returned to get the one that was made for him. That’s when Griffin confronted him. But this is your area of expertise. Picking up any artifact heat?”