He knew the number for his hardwired phone extension in the lab. He bought a virtual phone online and called it. It rang for several minutes, but he knew to wait. Eventually Pif answered.

“What? Sorry. Didn’t hear it, then couldn’t find it.” There were sounds of paper sliding to the floor, and muffled cursing. “Who is this?”

“It’s Sam.”

“You have to come in. Now.”

“Is anything wrong? You’re okay?” Petrovitch felt his pulse quicken.

“I’m okay. This note you left me…”

“Believe it or not, there’s something more important than that. Don’t go outside. In fact, call security and have them post a couple of guards at each end of the corridor. Tell them they need guns.”

“What have you done?”

“Pif: Tuesday was even worse than Monday. I have ruined my life so completely, so thoroughly, I can’t come back in. Ever. This is goodbye. But I had to warn you.”

There was almost silence: nothing but the crackles on the line and the sound of her breathing. “Sam, what about the science?”

“Sam will be dead shortly. Before he goes, he wants to say it was brilliant working with you and that he’ll miss you very much.”

“I can’t see any errors in your equation.”

“His equation. Petrovitch’s equation. And unless he’s invented a time machine, he won’t be coming back.”

There was more silence.

“Tell me,” he said, “I haven’t invented a time machine.”

“Not invented, as such. More described how it might be done. It’s the difference between Einstein and the Manhattan Project.” She even giggled.

“Pif, I can’t wait forty years. And this isn’t even why I phoned. Someone is trying to blindside me, presumably before coming after me with a pushka. Promise you’ll stay safe.”

She gave in. The whole tone of her voice changed. “Why, Sam? Why are they doing this to you?”

“Because I’m a bad man. You don’t need to know any more than that. There is one last thing you can do for me, though. Is the university network up or down? It’s isolated itself from the shit-storm that’s being kicked up my side of the node.”

“Up, last time I looked.”

“If I give you my password, can you copy some files to my supervisor?”

“You know I’m not supposed to do that, right?”

“Yeah. Pif: I’m going to be technically dead in a few hours. Violating my terms and conditions of usage isn’t going to bother me.”

“Hang on.” She dropped the phone to the desk and opened several drawers, trying to find her handheld computer. Petrovitch heard it chime as it was turned on, then the phone was scraped up again. “Okay.”

“Log on screen?”

“I’m there.”

“s-a-m-u-i-l-dot-p-e-t-r-o-v-i-c-h.”

“Done.”

“d-four-d-five-c-four-d-x-c-four.”

“I’m in.”

“See the folder called Simulations? Click that and tell me what you see.”