Out of the corner of her eye, Elena saw the mouse scooting back and forth across the top of her desk, pausing to raise himself on hind legs and sniff the air. He was nobody’s fool. Several million years of olfactory evolution told him that more food was in the offi ng, and he wanted his share.

She glanced at the bookshelf to see the toast had popped up. She broke off a piece for the mouse and tossed it in his cage. He scrambled immediately in that direction, his tiny ears catching the light like diaphanous wax.

“Hey,” she said, catching the little animal in his progress across two volumes of poetry and three Shakespearean criticisms. “Say g’bye, Tibbit.” Fondly, she rubbed her cheek against his fur before replacing him in the cage. The piece of toast was nearly his size, but he managed to drag it industriously towards his nest. Elena smiled, tapped her fi ngers on the cage top, grabbed the rest of the toast, and left the room.

As the corridor’s glass fi redoor whooshed closed behind her, she put on the jacket of her tracksuit and pulled up its hood. She ran down the fi rst flight of L staircase and swung round the landing by grasping the wrought iron banister and landing lightly in a crouch, taking the pressure of her weight in her legs and ankles, rather than in her knees. She took the second flight at a quicker pace, dashed across the entry, and flung open the door. The cold air hit her like water. Her muscles stiffened in reaction. She forced them to relax, running in place for a moment as she shook her arms. She breathed in deeply. The air-with the fog taking its origin in the river and the fens-tasted of humus and woodsmoke, and it covered her skin quickly with a watery down.