`The window?' Nordmann frowned. `I don't know

..Graves looked down at the street below, where an ambulance had pulled alongside the wrecked Alfa. A half-dozen cops and orderlies were trying to open the door, but it was still jammed shut. `Damn,' he said. `I wish he were still alive.'

`It probably wouldn't matter,' Nordmann said absently. He was staring across at the other building.

Graves said, `How good are my chances with the antidote?'

`Four thirty-five,' somebody said.

`Maybe one in two,' Nordmann said. `At best.'

`All right. Let's do it.'

`Are you sure?'

'What choice do I have?'

Nordmann considered this, then nodded. `Sit down,' he said. `I'll fix a syringe.'

He quickly filled a syringe with two solutions, one pale yellow, the other clear.

Graves sat and watched him. `How do I take it?'

`Intravenously.'

`You mean, in the vein?'

`Yes.'

`I can't possibly shoot into my veins.'

`You can,' Nordmann said, `if I tape on an IV line. Roll up your sleeve.'

Graves rolled up his sleeve, and Nordmann tied a rubber tourniquet around his arm. He slapped the veins to make them stand out. Then he turned back to the syringe. `I hope I've got this mixture right,' he said. He tapped the bubbles of air out of the syringe.

`So do I,' Graves said.

Nordmann attached the syringe to a piece of flexible plastic tubing. At the end of the tubing was a needle. `I'll put the needle into your vein,' he said, `and tape the syringe to your arm. Just before you enter the room, you can inject the contents.'

Graves felt the coldness of alcohol on his forearm, and then the prick of the. needle.

`Don't move,' Nordmann said. `Let me tape it down.' He removed the tourniquet, applied the tape, and stepped back. `Done.'

Graves looked at the equipment taped to his arm. `You sure this will work?'

`I told you the odds,' Nordmann said.

Graves stood up. `Okay,' he said. `Time?'

`Four thirty-nine.'

`Let's go,' he said, and ran for the elevator.

They came to the street and ran outside. By his side Nordmann was puffing, red in the face. Graves felt no strain at all; he was tense and full of energy. `Rope,' he shouted to a cop. `We need rope.'

The cop went off to get some.

`Hurry!'

The cop hurried.

Graves looked at Nordmann. `Listen,' he said. `I just had a thought. The gas leaked out of the nineteenth floor and killed those two cops. Right?'

`Right.'

`What's to prevent us from getting knocked off in the elevator as we go up to the twentieth floor?'

`Nothing,' Nordmann said. `It's a risk we have to take. If enough gas has leaked back into the building, we may die on our way up.'

`Is that all you have to say?'

Nordmann shrugged. `That's the situation.'

Two burly cops came over. One had a coil of white nylon rope over his shoulder. `Come with us,' Graves said. And he ran with Nordmann into the apartment building.

The elevator creaked up slowly. Graves fidgeted. Nordmann seemed very calm. The two cops looked at each other, obviously not understanding what was going on. They stared suspiciously at the syringe taped to Graves' arm.

They passed the tenth floor.

`Listen,' Graves said. `I had another thought. ZV is an oil, right?'

`Yes.'

`Well, when I get into that room, all the surfaces will be coated with oil. And deadly. Right?'

`Probably not,' Nordmann said. `It takes time for the droplets to settle. If the room is cleared of gas fast enough, the surfaces should be safe.'

`You sure?'

`I'm not sure about anything.'

They passed the fifteenth floor. Graves resisted the impulse to hold his breath. He looked at Nordmann. Nordmann crossed his fingers.

Seventeenth floor. Eighteenth floor. Nineteenth floor. Graves waited for the gas to hit him, but nothing happened. They came to the twentieth, and the doors opened.

`We made it,' he said.

`So far,' Nordmann said.

They hurried down the corridor.

`Time?'

`Four forty-two,' one of the cops said.

They came to Apartment 2011, the one directly above Wright's. The building had been evacuated and the door was locked. The two policemen threw themselves at the door. It didn't move. They tried again without success.

Nordmann went hurrying down the hallway and returned with a fire axe. He swung once at the door. The axe barely bit into the wood.

`Let me do that,' one of the cops said, and swung hard near the lock.

`Knock it down, knock it down,' Graves said.

It took time. There was no easy crash and splintering; the wood was new and strong and thick. Finally the cop managed to bash a hole large enough to admit his hand. He reached in and turned the lock. The door swung open, and they came into an apartment that was all chintz and doilies and heavy furniture.

Graves went directly to the window and flung it open. He looked out and down, feeling the hot, gusty August wind. He was sweating hard.

One of the cops tied the nylon rope around his waist.

`Tell me what I do,' Graves said to Nordmann, and pointed to the syringe.

`Okay,' Nordmann said. `You press that syringe to give yourself an injection of the antidote. You can push the plunger this far -' he touched the side of the syringe `- and be safe. More than that, and you will suffer effects similar to the gas itself. Clear?'

`Christ,' Graves said.

The cop cinched the rope tight around his waist.

`Remember,' Nordmann said, `that you're counteracting the effects of the gas and you must pay out antidote in relation to your exposure to the toxin. Clear?'

`What happens if I undershoot?'

`That's worse than overshooting. It's better to give yourself too much than too little. But not too much too much.'

`When do I begin to inject?'

`Just before your exposure to the gas. If you're exposed before injecting, you'll have only five or ten seconds of clear consciousness. So do it before.'

`Four forty-five,' one of the cops said.

Graves swung one leg over the window ledge.

`You afraid of heights?' Nordmann asked.

`Terrified,' Graves said.

`Good luck,' Nordmann said as Graves crawled completely over the sill and hung there for a moment with his hands.

`We've got you,' one of the cops said.

Graves let go and began his descent down the face of the building.

He tried to balance himself against the stone wall. It was remarkable how dirty the outside of an apartment building could be. His fingers scraped over a crust of dirt and grime and pigeon droppings. He tried not to look down, but once he lost his balance and twisted upside-down, so that he was descending head first. He stared straight at the ground.

The people were minute below him. He was vaguely aware of the hot wind whistling in his ears; it was the only sound he heard. He seemed completely isolated completely alone. He reached for the stones of the apartment wall with tense fingers. He slowly pulled himself around until he was upright again.

His descent continued more slowly. He checked his watch. It was 4:47. Plenty of time, plenty of time...

He was now just above Wright's window. He could see the interior of the apartment clearly - the two tanks, yellow and black, the connecting hoses, the equipment, the snaking cables and electrical lines.

`Okay,' Nordmann shouted. `Inject yourselfl'

Graves hung dangling and twisting on the rope, nineteen floors above the street, and tried to grab his own forearm. He was clumsy; his breath came in hissing gasps; the rope was tight around his ribs: Finally he got the syringe and pushed the plunger partway down.

`Go!' Nordmann shouted.

Graves kicked away from the wall, swinging out into space, and came back with his legs stiffly extended. The glass smashed under his feet, and he was swung smoothly, almost easily, into the apartment.

He dropped to the floor, coughed, and got to his feet. Immediately the acrid piercing sting of the gas invaded his nostrils and brought tears to his eyes. He felt light-headed. The antidote isn't working, he thought, and fell to his knees. He was gasping for breath. He looked up at the equipment, the tanks above him.

He was very dizzy. He injected more antidote. And then suddenly he was all right. His mouth was dry and he was still light-headed, but he was all right. He got to his feet and moved towards the tanks. At every moment he expected to hear the ominous hiss and sizzle of the releasing gas, but it never came. He stood in the centre of the room, with the wires and cords all across the floor at his feet and the white gas drifting gently out the broken window.

He disengaged the first valve mechanism, unhooking the solenoid trip wire. Then the other mechanism. And then he sighed.

It was done.

The mechanism could not release the gas; the tanks were isolated. He relaxed, blinked his aching eyes, swallowed dryly, and checked his watch. 4:49. It hadn't even been close.

`Graves!'

That was Nordmann, shouting to him from the floor above. Graves went to the window and looked up.

`You all right?'

Graves tried to talk, but a hoarse, dry croak came out. He nodded and waved instead.

`Can't talk?'

Graves shook his head.

`That's the effect of the antidote,' Nordmann said. `You'll be okay. We want to come down. Can you open that door for us?'

Graves nodded.

`Okay. We'll come down.'

Graves opened all the other windows in the apartment, then went back to the centre of the room and crouched over the three metal boxes. One was a timer; one was a battery; the third, when he turned it over, was a hollow shell, empty inside. He stared at it and shook his head. Another diversion - but it didn't matter now.

He went to the door and looked closely at the vibration sensors. They were just rubber suction cups from a toy bow-and-arrow set, with some wires attached. Totally phoney. He sighed.

Nordmann called from the other side of the door. `Graves? You there?'

Graves let him in. He had a glimpse of two San Diego cops sprawled on the floor in the hallway as Nordmann came into the room. `Gas is dissipated now, but those poor bastards got it full. How do you feel?'

Graves nodded, smiled:

`Dry mouth?'

Graves nodded.

`You'll be all right. Just don't inject any more of that stuff. You uncouple the tanks?'

Graves pointed.

`Well,' Nordmann said. `That's it, then.' He looked around the room. `Quite an elaborate setup.'

With a pluck! Graves pulled one of the rubber suction `vibration sensors' off the wall and showed it to Nordmann.

`I'll be damned,' Nordmann said. `Phoney as a fourdollar bill. But he really kept us guessing.'

Phelps came into the room. `What's going on here?'

`The tanks have been uncoupled,' Nordmann said. `There's no danger any more.'

`Good work,' Phelps said. He said it to Nordmann. Graves was angry about that, but he made no gesture. There was no sense in giving Phelps the satisfaction.

Phelps left. Somebody brought Graves a glass of water. Graves sipped it and wandered around the room, looking at the equipment, touching it idly..

`Well, anyway,' Nordmann said. `Congratulations.'

Graves shrugged.

`You're not accepting congratulations?'

Graves finished the water, tried his voice. `I'm not sure they're in order yet.'

`Why? Surely it's clear -'

`The double whammy,' Graves said. 'Wright is a master of it.'

`That may be,' Nordmann said, `but -'

`Then where's the second punch?' Graves said. He continued to wander around the room. When he came to the scintillation counter, he clicked it on. The machine chattered loudly like an angry insect.

`Damn,' Nordmann said. `Everybody out!'

Graves laughed and shook his head. Everybody left the room quickly. Phelps was outside in the corridor, talking with policemen who were removing the two dead bodies. `What is it now?' Phelps asked.

`A second punch,' Nordmann said. `Radiation in that room.'

Phelps smiled in total triumph. `We're prepared for that,' he said. He picked up a walkie-talkie. `We have a radiation hazard on the nineteenth floor,' he said. `Get the shielding up here.'

Graves and Nordmann exchanged glances.

`Oh,' Phelps said, `I'm not a complete fool.'

`Nobody ever suggested you were a complete fool,' Nordmann said.

It took two minutes for the policeman to arrive. He entered the room with the lead cases, which were carried on small, rolling dollies. He also had a pair of long tongs. He emerged a moment later. `All clear,' he said. `Two bars of some isotope. Shielded now.'

Phelps smiled. `As soon as we heard about the explosive,' he said, `I checked truck hijackings. There were two today: one for the explosive and another for the isotope.'

`Good work,' Graves said. He said it to Nordmann.

Phelps looked pained.

Graves and Nordmann went back into the room. Nordmann said, `Satisfied now?'

`Almost.'

Nordmann laughed. `You're a hard man to satisfy.'

`It's not me,' Graves said. `It's him.'

Nordmann looked around the room. `Well,' he said, `I don't know what you expect to find here...'

`Neither do L'

`You seem so certain.'

`I'm not certain. I'm just worried.'

Nordmann raised an eyebrow. `A triple whammy?'

`Maybe.'

`I think you're giving him too much credit.'

`Maybe.'

Graves continued to prowl around the room.

`Well,' Nordmann said, `in the meantime I think we'd better move these tanks apart. Just in case. I'll be happier when they're separated by a distance of several miles.'

`Okay,' Graves said. He was hardly paying attention, looking at the equipment in the room. `You know,' he said, `I can't get over the feeling that it's been too simple.'

`Too simple? It's been complicated as hell.' Nordmann put his arm over Graves' shoulder. `I think you're tired,' he said gently.

Across the room Lewis said, `It's five o'clock, gentlemen.' Everyone, including the cops, laughed. One or two of the men in the room clapped.

On the floor the timer wheel clicked once. There was a loud metallic snap.

The battery light blinked on.

The twin solenoids clicked to the `open' position.

And nothing happened, because the solenoids had been disengaged from the tanks.

`Well,' Nordmann said, `I can't imagine that there's anything else.'

`I guess not,' Graves said.

He and Nordmann left the apartment and walked down the corridor towards the elevators.

HOUR 0

SAN DIEGO:

5 PM PDT

At 5:02 Graves pressed the button for the elevator. The light didn't go on. He looked up at the floor numbers, one of which should have been lighted; they were all dark.