"It certainly isn't, though in Whitehall the paperwork is generally regarded as being mightier than the pistol. " George chuckled. "It does seem a bit silly to bring in a soldier and tell him to leave his gun behind. May I?" He lifted the pistol from the spring clip holster. It was an unfamiliar American make, in the usual.38 Special calibre, but surprisingly light, despite having a reasonable three-inch barrel. "Is this what the SAS sports, these days?"

"You get quite a choice."

George put the gun back carefully and waited, fascinated to see what else Maxim had in the briefcase. A sawn-off pump-action shotgun such as the SAS were rumoured to favour? A framed portrait of the dead wife? Like most good managers, George had the curiosity of a village gossip. But all Maxim brought out was Whitaker's Almanac, the Statesman's Yearbook and a pad of paper.

He's been swotting, George thought. "You're all fixed up with a place to live? – yes, you told me on the phone. And you're a Londoner anyway, am I right?"

"Mill Hill."

"That'll help. And about your little boy, he's what age now?"

"Christopher, he's ten. He's down with my parents in Littlehampton. They retired there a couple of years ago, and they've found him a school locally." His voice was quite calm.

"Good. I suppose you'll be down there most weekends. You'll always let the switchboard know where… no, I said that already, didn't I?"

I need a drink, George thought.

"What am I going to be doing here?" Maxim asked.

"Yes. Well. Roughly speaking… at the Headmaster's discretion, you get first crack at any security problem we think is likely to, or might… cause embarrassment in the area of defence, as you might say…"

Sir Bruce had told Maxim: "I can't find out what the hell they want you for, but they've had a bad case of wet knickers since before Christmas so maybe they want somebody to piss on when the pot's full. You've been in the Army quite long enough to be used to that."

When George had finished, Maxim said: "I'm not a detective."

"No, we don't expect that. But you've done the Ashford course, haven't you? You can organise a surveillance and so on?"

"I've got more theory than practice."

"Well then… I tell you what-" George looked at his watch; "-why don't you and I slide over to Boodle's and continue the briefing there?" He looked at Maxim hopefully. Thirstily.

Maxim gave a quick smile, but wondered if this was going to become a regular invitation. George picked up the phone and told the switchboard where they'd be. At least nobody could accuse George of being a secret drinker.

"And one thing you won't be doing," George added, "is hounding deputy under secretaries… damn it, I'm sounding like a bloody Quaker. Whenever you ask them what they believe in, they start listing the things they don't believe in, beginning with the Scarlet Woman. But now I suppose it'll turn out you're a Quaker… no, I suppose not, in your job."

"My sister married a Friend. I know what you mean." And maybe, Maxim thought, I'm as close to Quakerism as to anything. Jenny would have had something to say about that, but we never got around to it. Oh, Jenny, the things we never got around to.

George led the way out.

Maxim had run a company office in a wrecked armoured personnel carrier and the broom cupboard of a Belfast school, so a whole box-room to himself was pure luxury, and like an alley cat he stretched out and enjoyed this temporary treat. He also learned that 'room' was the right word. In Number 10 an 'office' was the Private Office, the Political Office, Press Office, and so on, sometimes whole suites of rooms.

But for all that, it went on being a house. There was an air of quiet busyness, a polite official scurrying behind every wainscot, yet in its decor, the pictures on the walls (nothing so crude as maps or charts of organisation), the whole style, it was still the town house of a duke who had occasionally to pop up to town to govern the nation instead of the partridges. The Housekeeper's Office, afraid that Maxim might forget he was a soldier, offered him a selection of solely military pictures for his own room. He chose a lively watercolour of the Mahratta Army at Seringapatam and put up maps of London and Europe on the other walls. The Housekeeper's Office expressed Unvoiced Disapproval.

"Lunch," George had warned him, "is not one of the great thrills of Whitehall. Just thank your choice of career that you aren't entitled to eat in most of the civil service canteens. All fried fish and spotted dick, just as nanny used to make. But I suppose if you've spent twenty years eating in the nursery, prep school, public school and some Oxbridge hall, your taste buds must look like the Dutch elm disease."

Whitehall was, Maxim soon saw, two Whitehalls, living in the frigid intimacy of an unconsummated marriage. In between the ponderous ministry buildings, the Abbey, the Palace of Westminster itself, there had developed an undergrowth of worn-out pubs, greasy hamburger bars and small shops selling overpriced models of London buses and Big Ben.

Only the tourists bridged the gap between the two Whitehalls, standing in the January rain to photograph anybody coming out of the multi-million-times photographed doorway, then dodging across the road to buy a fresh film, a stale sandwich and an ashtray shaped like the Imperial State Crown. Not lunchtime country.

Maxim met the Prime Minister on the third day. It was a disappointing meeting but doomed to be, because Army officers have an exaggerated respect for politicians. It can take at least ten years to design, develop, test, redesign, re-test, produce and issue a new rifle. It can take a politician ten minutes in Cabinet to argue that it's the wrong rifle and get it cancelled. The Headmaster – George called him that to his face and he seemed to like it – was shorter than he looked on television, his Scottish accent was stronger, and he spent most of the time talking about his experiences with the 51st Highland Division just before St. Valйry in 1940. Maxim was used to people learning he was an Army officer and then recalling their own military careers, however brief. He was intrigued to find that it applied to Prime Ministers as well.

The PM didn't tell Maxim any more about what he was supposed to do, so for ten days he did nothing except re-arrange his room, try to work out the command structure in the house, and read some innocuous files that George sent up. Then came what was later known as the Day of the Grenade.

The first Maxim knew of it was one of the girls from the Political Office put her head round the door and said breathlessly: "You're not to go downstairs. I mean not to the hall, it's a bomb, I think they said." At the same time, the phone rang. Maxim smiled quickly at the girl, who smiled back and studied him a few seconds longer – it was the first chance she'd had – and then rushed off without closing the door.

It was George on the phone. "Not to panic, old boy, but somebody's thrown a grenade in through the front door."

"A grenade? I didn't hear anything."

"It didn't go off, not yet anyway. If you do hear anything, it'll be the Security Officer committing hari-kiri. They've sent for the bomb squad, so all you have to do is nothing."

"What sort of grenade?" Maxim asked.

"How the hell do I know what sort? I haven't gone and interviewed the bloody thing!" George slammed the phone down.

Maxim thought for a moment, then walked out and downstairs. At the end of the corridor leading to the entrance hall, a security guard stopped him. "There's an unexploded grenade down there sir…"

"Yes. I know a bit about grenades. I just wanted to see it."

"The bomb squad's on its way, sir…"

"It's all right, I'm not going to practise penalty kicks with it." He stepped around the guard, who grabbed his elbow and then found his own arm almost twisted from its socket. Maxim's reaction had been quite instinctive.