“And Kay and the rest believe we can actually do something about this? Forgive me for saying so, but this seems out of even Cam’s league.”

Alison shrugged. “This is where I run out of maths, frankly, but they seem to think that a deft enough hand on the scales could result in the timelines becoming independently stable, like putting a keystone into place on an arch. We couldn’t have built the arch ourselves, none of us, but the Ediacaran had the scaffolding to do it. Except they were the scaffolding. They’re holding the whole thing up by hand, so that it topples the moment they stop. Khan reckons there’s an equation out there that would let us nudge everything into a stable alignment that just holds itself up. A tiny, precise application of force, something we can achieve at our little level, which would result in the universe…”

“Leaning against itself.” Julian had a mental image of John trying to build a proper campfire at scouts, increasingly frustrated as the sticks kept falling down.

“All the timelines distinct and stable. And then we can all get on with our lives.” The way Alison said it, he knew that she thought they’d be stuck here, too, locked out by their own success. He put an arm about her shoulder, ostensibly to console her but more to console himself. He needed the luxury of human contact, the infinite reassurance that he didn’t have to face the madness alone. Alison leant into him, and the chill of her extradimensional connection ebbed, replaced by the welcome warmth of her body heat.

“Spiker,” she said, and then nothing else. He found his arm had slipped down until it was about her waist, and her hip and thigh were pressed against his. Her head was turned slightly, lips an inch from his cheek so that he could feel the flutter of her breath. All terribly genteel and polite. And yet, under the skin, he found that he wanted her in a way that was more powerfully physical and erotic than anything he had allowed himself to feel in a decade. We are at the end of the world. And no one would ever know. Right now, there was nothing preventing the two of them finding a chamber within Cam and tearing each other’s clothes off.

Julian felt the moment stretch, excruciatingly aware of Alison’s own stillness. Knowing that she was exactly there, at that same crossroads, waiting to see what path they would take. If he said yes then she would most likely say yes too. They would have committed themselves to that one thing that had been the elephant in whatever room they shared for years. Despite all the recent lessons he’d had about his infinitesimal place in the cosmos, Julian fancied he could hear the universe holding its breath.