Augustino wasn't at headquarters or the Tech Area. In the commissary, Joe heard the captain had been seen driving on Bathtub Row. Bathtub Row had nothing but long afternoon shadows. No maids hanging clothes or walking babies. There were no sounds except for jays and drifting shouts of a softball game on the playing field. Walking past Fermi's cottage and Jaworski's stone house, he remembered that Snow White and the Seven Dwarfs was the early movie. Everyone with kids, even Kitty Oppenheimer, was at Snow White.

At the end of Bathtub Row a garden of poplars and spruces lent privacy to the Oppenheimer cottage. Augustino was coming out of the kitchen door and there was something about the way he moved that made Joe silently stop and watch. Augustino carried a small reel of white wire finer than the electrical wire used on the Hill. He let himself out of the back garden gate and slipped into the trees.

The boy's scooter still sat in the flower bed. It looked rusted to the spot and the flowers lay flat and dead. Joe knocked softly at the door. It was unlocked. The living room's casement windows afforded sunlight that reflected off a hardwood floor and whitewashed stone walls. The furniture was Spanish rustic and rattan, an easy chair with a laurel pattern, stand-up ashtrays, scrapes on the sofa, bookcases, Santiago pottery on the mantelpiece. Nothing apparently out of the ordinary.

Kitty didn't like maids re-ordering the bedroom. A four-poster stood over ashtrays, open books, loose butts, water glasses. There was a Picasso lithograph on the wall, a dishevelled bookcase. No white wires along the skirting board.

The study had a Spanish fireplace in the corner, a desk of spreading papers, two ashtrays of cigarette butts and a third ashtray with two pipes, a meerschaum and a briar. Hanging pictures of Krishna and a sailboat off a beach.

The nursery had been a sun porch and still had the yellow light of the porch. A crib at one end and a bed at the other. Teddy bears on a scatter rug. A case of children's books with a top row of German novels. Kitty employed a German nurse.

Joe returned to the living room, moving round the periphery and lifting chairs, tables, sofa. As he moved the bookcase, he saw the white wire that emerged from the edge of the floor, rose almost invisibly up the whitewashed wall and led into the back of the case. He searched through the records on the bottom shelf: Bach, Beethoven, Faure. He spilled out the books above: Austen, Unamuno, Jeune Fille Violane, Thermo-dynamique, Upanishads, The Interpretation of Dreams. Behind Freud was the microphone, a wire-mesh button no larger than a dime. He snapped it off.

Tracking the wire to the boiler room in the basement, he found a new electrical connection off the junction box and a radio hidden behind a bin of soft New Mexican coal. He took the radio, went back to the living room and neatened up the books. By the time he left there was no sign of his visit or the captain's, nothing but resonance, a fading disturbance like two trails in a cloud chamber.

13

      The Utah sky was different. Scrubbed clean. Saline. Instead of vultures, gulls. Fort Douglas, Salt Lake City, was different from Los Alamos because Douglas was so quiet. No booms from a mesa. No Indians. No women. Just the olive drab lethargy of the rearmost echelon of the United States Army.

The motor pool was a Quonset hut with open wings of galvanized steel over shadows and the glow of welders. Joe and Ray Stingo waited at the pumps. A noon sun lifted the reek of petrol off the tarmac. Ray's pompadour, usually sculptured with Wildroot, hung like crepe.

"Chief, you should've fought."

"They asked for you and me."

"Why?"

Joe walked to the other side of the petrol pumps rather than argue. He and Ray had flown in from Santa Fe the night before and all the way Ray had asked the same question: why?

"The Texas kid killed Shapiro," Ray said.

"That's what I heard."

Ray followed Joe round an oil can.

"Captain Augustino can't have wanted you here."

"The captain never said anything to me about it." Joe hadn't spoken to Augustino since Oppy's cocktail party the week before. "Look, while Oppy's still in Washington, I'm available for this."

"But what about me?"

"You'll be okay."

A convoy rolled towards the pumps. Army sedan, truck, ambulance and tail sedan had started out the day before in Hanford, Washington, and had come 550 miles. Fort Douglas was where the teams switched. "Too late," Ray moaned.

The schedule was strict. As soon as the lead sedan was at the first pump, four CID lieutenants jumped out and a fresh quartet took their place. Mechanics swung wearily out of the repair truck, a slope-fendered Dodge 6x6. The two men Joe and Ray were replacing both pulled the ambulance handbrake and jumped out. Joe and Ray climbed in, Joe behind the wheel. The rear of the ambulance was green Army. No white cross. No cots, no stretchers, no medicine. Only two fold-down seats and, farther back and taking up most of the space, an open steel square, four feet to a side, bolted to the floor and braced to the walls. Restraining straps of 1,000 lb-test nylon reached in from the eight corners of the square and hooked on to a 50lb spun steel canister suspended at the centre. The canister was lined with graphite and lead, and bore, inside a hollow of moderating water, a ten-gram, lead-coated, stainless steel capsule of jelly-like plutonium nitrate that drivers called the slug. The two sergeants from Hanford had bright eyes and stubble and the air of men returned from the dead.

"Want some bennies?" One came over to Ray's window and offered a handful of white pills. Ray took three and swallowed them. "You better take this, too." He handed in the Tommy gun that the co-driver was supposed to carry.

"Secure the convoy!" the lieutenants shouted at each other. They were boys right out of college and straight into Intelligence and would never see war. As they ran around with .45s and submachine-guns they reminded Joe of the sort of kids who brought baseball gloves to big league games. Mechanics clambered into the truck. Its back was stuffed with ambulance, car and truck spare parts in case there was a breakdown on the way. The orders were - as always, from Groves - no stopping. "Let's for Chrissake go." Ray clutched the Tommy gun. Hair clung to the sweat on his forehead. His face had closed down to a bleak and dangerous glare. He refused to look back at the suspended, eight-armed canister riding in the rear of the ambulance.

"Wait a second, men."

A white-haired man in a tweed jacket and carrying a clipboard bounded out of the garage towards the ambulance.

"Santa!" Joe said.

"I'll kill him," Ray said.

Santa was the Hill psychiatrist. He'd always seemed to be part of the furniture at the lodge, an amiable headshrinker on hand to offer security-cleared emotional assurance to any longhair with the blues. Joe couldn't figure what Santa was doing at Fort Douglas. He expected the lieutenants to block Santa's way because no one outside convoy personnel was allowed near the ambulance, but the officers waved Santa on.

"Permission to come aboard?" Santa took a letter from the clipboard and handed it through Ray's window to Joe. The letter was a pass for Dr Delmore Bonney to accompany the drivers of Army ambulance YO3 from Fort Douglas to Site Y (Los Alamos), and the order was signed by both Oppy and Groves.

"I think you'd be more comfortable in one of the cars." Joe gave the letter back.

Santa shrugged happily.

"Orders are orders. Sometimes even civilians have to suffer."

"Sergeant Stingo isn't feeling too good. It could be infectious," Joe warned.

Santa raised white eyebrows.

"It could be psychosomatic."