It starts with a bubble in my stomach; the kind you get when you’re breaking atmosphere and started edging micro-gee. My inner ears tell me that we’re turning, that the floor is becoming the wall across the walkway from me, and that I’m strapped to seats on the ceiling. Belts float in the air around me, coiling like they’re in freefall. It lasts half a heartbeat, less.

And then it’s done.

At first, all I can hear is the rush of blood behind my ears. Everything else come in a second later, but choppy, like it’s being filtered through a turbofan. The shutters climb our windows, and patchy light creeps in from outside, the air around us suddenly thick with dust. Lear is exactly where we left him, his grip denting the seats. Salt hasn’t moved far, but I can see raised veins and sheets of sweat. He held himself in place through all of that, boots and fingertips and sheer force of will. Hail is looking out the window.

I follow her gaze. “What the fuck was that?”

Outside, steel screams and sirens wail, smoke rises in the distance. Containers lie scattered across the hangar floor, cracked open or perched on piles of wreckage. A crane lies on its side, neck broken. Fire crews tear along the hangar’s internal highways, and drones swarm above, lines of foam spewing from their nozzles. A shuttle hangs loose in the gantries above, gushing fuel that falls like rain.

“Christs,” mutters Lear.

“Christs is right,” replies Hail, eyes unfocussed. “That’s another one.”

“Another what?”

She doesn’t look back at me. “Tide. A string of gee waves, starting smaller than you can feel, but ramping up to one huge burst, exponential. The last one big enough to give you a feel like flying.”

“You said ‘another.’”

She nods. “The first was about two weeks ago. The outstations figure they’re coming from somewhere deeper in.”

‘Deeper’?

But Hail’s changed focus again. She perks up, listening to something I can’t hear. Someone is calling in over the net, piped in through the wetware in her ears. She sheds her restraints, stands to pace the train. “Then I need you to get someone to override this car. We’re still clamped,” she says, stooping to look out the windows again.

The locks clatter beneath us and the train pulls off, sudden enough to make Hail stumble. She collects herself and keeps pacing as if nothing happened. “Thank you. We’re moving now; ETA is a couple of minutes. Try and contain it until I arrive.” She cuts the line with a blink and slumps back into a seat. “Hold on,” she whispers.

I pop my restraints, and wave a hand to catch her eyes. “What’s happened?”