Lixue is thorough, picking through the guts of abandoned electronic devices for anything worth saving. She overturns the beds, ripping apart pillows and cushions and checking the spaces between. Suddenly, the rhythmic sounds of her rummaging quiet. I turn to find her talking in a low voice, one hand pressed to her transmitter. Her eyes snap to mine. “It’s Zahra. She says Sampson and Sommers boarded a flight out of Mexico City. They’ll be landing at Heathrow in twelve hours.”

Which means they’ll be at our front door soon. “Then you’d better hurry and find me that damn crystal. I want it in my hands before Jack makes it down here.”

“Yes, sir.” Lixue disconnects and starts ransacking Jack’s closets and drawers. It has to be somewhere in this room. We’ve searched everywhere else.

“Chronos, in here.” Lixue drags a metal footlocker from the bottom of the closet, kicking aside rolled tubes of drawing paper as she hauls the box to the middle of the room.

I stoop to pick one up. The curled pages are reluctant to unroll, and the dark, sketched pencil lines smudge where I hold the edges down.

Barely legible notes fill the margins. The intersecting lines are marked with x’s and question marks. I recognize the shape of the structure in the drawing before I’m able to decipher Jack’s handwriting. A circular hall fills the center of the first page, the radiating spokes of each wing spreading over the next four sheets.

These are sections of a map. A map of the Observatory.

The pages are marked with dates, as details were added or erased over time. The earliest goes back to 1989. The section of the catacombs under the north wing is roughly sketched, the tunnels under Jack’s dorm room meticulously labeled. Some are marked with obvious dead ends. Others are left unfinished with question marks.

He’s been plotting the exits from the Winter wing—tunnels and access points, stairwells and closets—since the year he first arrived. Before Fleur even got here. As if he was itching to break free of this place since day one. But the catacombs were off-limits to Seasons and Handlers, which means Jack had help.

And I can guess who it was.

I toss the maps to the floor. “I want every tunnel under the north wing searched as soon as we’re done here.”

“What should I do with these?” Lixue squats in front of the open footlocker. Something clear and shiny dangles from her hand, casting rainbows over the floor. Lixue starts as I snatch the object from her hand, but it’s just a Christmas ornament, a snowman bearing no resemblance to the missing crystal from the staff. One segment of the snowman’s body is too small, another too large, all of them too round to be the eye.