The poor lad's in for a royal bollocking after parade, Maxim thought. Over-selling in the face of the customer. Bad show, or its American equivalent.

The talk decentralised again, and he was looking for a place to put down his cup when Brock touched his shoulder. "The Professor's agreed to join us in a little end-of-trials dinner party at an inn just over the hill. We've got rooms booked there, so he'll probably stay the night, but maybe you'll be looking up old friends in Warminster?"

Perhaps there was no politer way of putting it, but Maxim had his orders. "I have to stay with the Professor, I'm afraid. Obviously not at the dinner, but if he's spending the night there, I'll have to as well."

"You just have to, do you?" Brock's temper wasn't quite restored.

"That's right."

Brock suddenly grinned. "Okay, Harry. Don't worry, we'll fix you a room."

"Next door to the Professor, please."

The hotel was an old coaching inn – most were, in that area – north of Warminster under the steep escarpment of the Plain. With its creaking corridors, low oak beams and the horse-brasses and hunting horns in the bar, it looked very English, particularly to those who weren't. Maxim changed quickly into plain clothes and went down to ring George from the phone at the desk.

"The trouble is," he explained, "I feel I'm embarrassing him without really sticking close enough to do the job properly."

"Well, that's hard bloody luck on both of you. You'll just have to get used to playing gooseberry and so will he. He's a national asset, now. Stick as close as you can and think of England."

As advice, it didn't help, but Maxim felt slightly cheered. He prowled around the hotel inside and out, then found a seat in the bar from which he could cover the front door. He had the shoulder holster on under his jacket.

By dinnertime, the Seddon party had grown: Brock's wife, a lean blonde with a Texan accent, together with another husband-and-wife from the London office and the elderly defence correspondent of a national newspaper. Three very good-looking girls who obviously didn't belong to the hotel helped pass around drinks in the dinning-room annex.

Maxim ate almost alone in the dining-room itself and dawdled over the meal as long as he could, although it was nasty even by the standards of famous old coaching inns. Then he went back to the bar and sipped a pint of beer until the party broke up in a burst of laughter and cigar smoke just before midnight.

"Ah, my faithful watchdog!" Tyler was a little drunk. "It's all right, Harry, you can go to bed now."

But: "A last Drambuie, Professor?" Brock suggested, so they all had a final liqueur at the bar. The landlord, doing the barman's job to save overtime by now, was happy to stay open as long as Seddon Arms wanted to drink. Maxim was beginning to guess at the scale of 'hospitality' which the arms business could afford.

They got to bed at about half past. Another snag about old coaching inns is that the old coaching lines they once served have become main-line lorry routes. But it wasn't a lorry that shook Maxim awake, just the double bang of a gun.

He was on his feet, revolver in hand, before he had worked out what gun and where. Probably a double-barrelled shotgun, and close. As close as the next room?

He lunged at Tyler's door. It was locked. He yelled: "Professor!" and got no answer but heard something move and there was a small mat of light at his feet, coming from the ill-fitting door. There was a heavy conical fire-extinguisher hanging on the opposite wall. He tore it free and smashed it into the door-handle in one sweep.

Tyler peered at him, bright-eyed and unsleepy, from the rumpled big bed. "Harry, what is going on here? What are you-"

But Maxim had slipped into old ingrained habits: looking for an armed man you either moved very slowly or very fast, and he was already moving fast. He threw a chair at the curtains and hit nothing, barged open the bathroom door, opened the wardrobe-If she had been chosen for looking decorative, Seddon Arms had proved themselves good choosers, assuming they hadn't seen her stark naked, as Maxim now did. Well, not really stark, since somebody had been drawing interesting patterns on her in lipstick. She looked at Maxim with a small, cold smile.

He said: "Do you want to come out, or shall I close the door?" It sounded silly, but it was the only polite remark he could think of. She walked regally past him and shut herself in the bathroom.

He glanced back at Tyler, who was clutching the sheets up to his chin, but knew he was in the wrong place. There was no smell of gunfire.

In the doorway, he bounced off Brock, also wearing just pyjamas. Behind was the young aide, who had shyly waited long enough to get on a dressing-gown.

"Nothing wrong in there," Maxim said, pushing past.

"I guess outside, then…"

Maxim grabbed his shoes and combat jacket from his room and met the landlord at the top of the stairs, twittering like a lost starling chick. Maxim shoved him back down. "Get that back door open."

"But there's somebody outside, he's just waiting to-"

"Or I'll throw a chair through the bloody window. Now move!"

The landlord had spent years catering for Army celebrations and arms company parties, but Maxim was actually holding a gun. He unlocked the door with shaking hands.

The night was far darker and quieter than a London night and in his pyjamas Maxim felt both vulnerable and ridiculous. But I know more than he does. Whoever it is out there isn't as good as I am. You believed that or you looked for a job selling encyclopaedias. He began to circle the building anti-clockwise, wanting to come up on whoever from the right. For a right-handed man it is more difficult to swing a long gun to the right than to the left.

Unless he's standing facing the hotel, of course, which puts you on his left. Or he may be left-handed anyway. Maxim shivered.

A lorry rumbled past, shaking the ground, and he moved ten yards before the noise had faded. There was a stone wall about the height of a desk just ahead, he recalled. But there's a bush that breaks the sharp line of it. Get behind that…

Somebody moved on the porch. Maxim carefully brought the gun up, cupping it in both hands. The figure stepped back, just a black silhouette against the near-blackness of the sky, but carrying something long…

Maxim took a slow breath. "Drop the gun or I shoot."

The figure turned, not fast, but not dropping the long thing. "Are you the police?"

"I said drop it!"

Suddenly Maxim got tired of playing a TV detective. He lifted the revolver, remembering to shut his eyes against the flash, and squeezed off a shot towards the sky.

There was a moment of silence, then the night tore apart in light and thunder. The bush above Maxim shattered, sprinkling him with twigs, and for a moment he had to try and think if he were hit or not. But it had been another double bang, certainly a shotgun and almost certainly empty now, so then he was over the wall and rolling up with the pistol pointed…

Maxim said, very calmly: "Put the gun down."

Farthing put it down. It was a double-barrelled shotgun, all right.

Maxim walked quietly up and put his pistol against Farthing's forehead. For a long moment they stood there, and perhaps it was Farthing's trembling that made the gun shake in Maxim's hand.

"Don't ever shoot at a soldier," Maxim said softly. "It gives him funny ideas about wanting to shoot back."

"Oh, I didn't mean to… I thought you were from MoD."

"Where else do soldiers come from? Spread yourself against the wall. Just like on the telly."

Farthing leant against the wall while Maxim searched him. There were three unfired 12-bore cartridges in one pocket.