He opened the door slowly, so as not to disturb Pif. She was precisely where he’d left her, crouched over her desk, staring at sheets of minutely detailed equations. If she knew he was there, she made no sign of it.

He threw his bag on his chair, collected her empty mug and rinsed it out using bottled water and his fingers, pouring the brown-stained contents into a pot plant. Then he busied himself making coffee: spooning the granules, boiling the water, stirring and breathing the steam in.

She still hadn’t moved. Even when he delivered the fresh mug to her desk, setting it down exactly on the sticky ring left by the previous brew.

“Pif? Are you catatonic again?”

One eye twitched.

She got like this sometimes, caught up in a recursive math loop that rendered her higher functions incapable of voluntary action. Petrovitch waved his hand in front of her face; her eye twitched faster.

“Yeah, okay. A drop of the hard stuff should sort you out.” He went behind her desk and opened the drawer that contained the bottle of lemon juice. He spilled some into the palm of his hand and brought it close to her nose.

She blinked, made a face, and recoiled.

“Sam,” she said. “How long?”

“No idea. I just got in.”

She stretched extravagantly, and Petrovitch disposed of the juice the same way he’d gotten rid of the coffee dregs. She gave a cry of pain.

“You okay?”

“Pins and needles. I’ll be fine in a minute. Ow ow ow.”

“How you don’t get pressure sores is a miracle.” He wiped his hand on a suitable leaf and used a wet wipe to clear the stickiness away.

“My neck hurts too.”

“You’re not safe to be left on your own.” He pulled out two cellophane-wrapped pastries from his bag. “They’re a bit squashed, but they’re fresh. Ish. At least, I only just bought them.”

“Give me a minute to boot up.” She dug her knuckles into her left thigh and grimaced. “What’s the time?”

“Half eleven.” She clearly expected him to carry on. “On the Tuesday.”

“Good. I thought I’d wasted a whole day.” Pif tried to stand, using her desk for leverage. She wobbled like Bambi, then managed a semblance of upright. “I have good news and bad news.”

Petrovitch passed her a pastry. “Good news, please. My life is so irredeemably pizdets that I can’t cope with anything bad.”

“We haven’t got any competition. I may have been as subtle as a brick casing out the opposition, but we’re in front.”

“Stanford?”

“Out of sight.” She took a few tentative steps and didn’t find them too painful. “Are you sure you don’t want the bad news? I mean, after yesterday, how could it get worse?”