The third floor up was crammed with women sewing shirts, their heads bent, eyes straining to see, fingers flying with needle, thread weaving in and out. A man with pincenez glasses balanced on his nose glared at the sergeant and hissed his irritation, wagging his finger like a schoolmis- tress. Monk longed to hit him for his meticulous cruelty, but he knew it would have done no good. One piece of paltry violence would not relieve anyone's poverty. And he was after Caleb Stone, not one wretched sweatshop profiteer.

The first room on the top floor up was occupied by a one-armed man, carefully measuring powder into a scale. In the next room three men played cards. One of them had thin gray hair and a stomach which bulged out over his trousers. The second was bald and had a red mustache. The third was Caleb Stone.

They looked up as the sergeant opened the door. For a moment there was silence, prickling cold. The fat man belched.

The sergeant took a step forward, and in that instant Caleb Stone saw Monk behind him. Perhaps it was some look of victory in Monk's face, maybe he recognized the sergeant. He climbed to his feet and lunged towards the win- dow, throwing himself out of it with a shattering of glass.

The fat man rolled over onto all fours and charged at Monk. Monk raised his knee and caught him in the jaw, sending him reeling backwards, spitting blood. The other man was locked in a struggle with the sergeant, swinging backwards and forwards together like a parody of a dance.

Monk ran over to the window and smashed the rest of the glass out of the frame, then leaned out, half expecting to see the figure of Caleb broken on the pavement four stories below.

But he had forgotten the twists and turns of the stairs. They were facing the back of the building, and beneath him was the roof of a high wooden shed, not more than twelve feet away. Caleb was running across it, agile as an animal, making for the opposite side and a half-open window.

Monk scrambled over the sill and leaped, landing with a jar that shocked his bones. Within a moment he was on his feet and racing after Caleb, the shed roof rattling under his weight.

Caleb swung around once, his wide mouth grinning, then he jumped for the window and disappeared inside.

Monk went in after him, finding himself in another cold, suffocating room just like those he had left. Three old men sat with bottles in their hands around a potbellied stove smelling of soot.