The Green Day

For the first time anyone remembers, the wards run green — the old custom that spring has arrived. Everyone wears green, the greenhouse opens, the whole Academy warms. But under the green wards, the veil thins, and a rainbow-door grows in the meadow — a naturally thin place, the same kind as the thin night. The crew discovers it, and must choose whether to walk it: the door's pull into the strange, against the warmth of the green day they're standing in.