I WAS taking a Martini across the room to my wife, who was still chatting with our host, Amos Darrel, the physicist, when the front door of the house opened and a man came in to join the party. He meant nothing to me-but with him was the girl we'd called Tina during the war.

I hadn't seen her for fifteen years, or thought about her for ten, except once in a great while when that time would come back to me like a hazy and violent dream, and I'd wonder how many of those I'd known and worked with had survived it, and what had happened to them afterwards. I'd also wonder, idly, the way you do, if I'd even recognize the girl, should I meet her again.

After all, that particular job had taken only a week. We'd made our touch right on schedule, earning a commendation from Mac, who wasn't in the habit of passing them around like business cards-but it had been a tough assignment, and Mac knew it. He'd given us a week to rest up in London, afterwards, and we'd spent it together. That made a total of two weeks, fifteen years ago. I hadn't known her previously, and I'd never seen her again, until now. If anyone had asked me to guess, I'd have said she was still over in Europe, or just about anywhere in the world except here in Santa Fe, New Mexico.

Nevertheless, I didn't have a moment of doubt. She was taller and older, better looking and much better dressed, than the fierce, bloodthirsty, shabby little waif I remembered. There was no longer the gauntness of hunger in her face or the brightness of hate in her eyes, and she probably no longer concealed a paratrooper's knife somewhere in her underwear. She looked as if she'd forgotten how to handle a machine pistol; she looked as if she wouldn't recognize a grenade if she saw one. She certainly no longer wore a capsule of poison taped to the nape of her neck, hidden by her hair. I was sure of this, because her hair was quite short now.

But it was Tina, all right-expensive firs, cocktail dress, and hairdo notwithstanding. She looked at me for a moment without expression, across that room of chattering people, and I couldn't tell if she recognized me or not. After all, I'd changed a little, too. There was more meat on my bones and less hair on my head after fifteen years. There were the other changes that must have left visible traces for her to see: the wife and three kids, the four-bedroom house with the studio out back and the mortgage half paid up, the comfortable bank account and the sensible insurance program. There was Beth's shiny Buick station wagon in the driveway outside, and my beatup old Chevy pickup in the garage back home. And on the wall back home were my hunting rifle and shotgun, unfired since the war.

I was an ardent fisherman these days-fish don't bleed much-but at the back of a desk drawer, kept locked so the kids couldn't get at it if they should get into the studio against orders, was a gun this girl would rembar, the little worn Colt Woodsman with the short barrel, and it was still loaded. And in my pants was the folding knife of Solingen steel that she'd recognize because she'd been present when I'd taken it from a dead man to replace the knife that he'd broken, dying. I still carried that, and sometimes I'd hold it in my hand- closed, of course-in my pocket as I walked home from a movie with my wife, and I'd walk straight at the groups of tough, dark kids that cluttered up the sidewalks of this old southwestern town at night, and they'd move aside to let us pass.

"Don't look so belligerent, darling," Beth would say. "Anybody'd think you were trying to pick a fight with those Spanish-American boys." She'd laugh and press my arm, knowing that her husband was a quiet literary individual who wouldn't hurt a fly even if he did write stories bursting with violence and dripping with gore. "How do you ever think of these things?" she'd ask, wide-eyed, after reading a particularly gruesome passage about Comanche massacre or Apache torture, generally taken pretty straight from the sourcebooks, but sometimes embellished with some wartime experience of my own, set back a hundred years in time. "I declare, sometimes you frighten me, dear," my wife would say, and laugh, not frightened at all. "Matt is really quite harmless in spite of the dreadful things he puts in his books," she'd assure our friends happily. "He just has a morbid imagination, I guess. Why, he used to hunt before the war, before I knew him, but he's even given that up, because he hates to kill anything except on paper…

I'd stopped in the middle of the room. For a moment, all the cocktail-party sounds had faded completely from my consciousness. I was looking at Tina. There was nothing in the world except the two of us, and I was back in a time when our world had been young and savage and alive, instead of being old and civilized and dead. For a moment it was as if I, myself, had been dead for fifteen years, and somebody had opened the lid of the coffin and let in light and air.

Then I drew a long breath, and the illusion faded. I was a respectable married man once more. I'd just seen a ghost from my bachelor days, and it could make quite an awkward little situation if I didn't handle it right, which meant acting just as naturally as I could, walking right up to the girl and greeting her like a long-lost friend and wartime comrade, and hauling her over to meet Beth before any awkwardness could develop.

I looked for a place to park the Martinis before starting over there. The man with Tina had removed his wide-brimmed hat. He was a big, blond man in a suede leather sport coat and a checked gingham shirt with one of those braided leather strings around the neck that Western males tend to wear instead of ties. But this man was a visitor-his outfit was too new and shiny, and he didn't look comfortable in it.

He reached for Tina's wrap, and as she turned to give it to him her free hand lifted casually and gracefully to brush the short dark hair back from her ear. She wasn't looking at me now, not even facing my way, and the movement was wholly natural; but I hadn't quite forgotten those grim months of training before they sent me out, and I knew the gesture was meant for me. I was seeing again the sign we'd had that meant: I'll get in touch with you later. Stand by.

It was a chilling thing. I'd almost broken the basic rule that had been drilled into all of us, never to mccognize anybody anywhere. It hadn't occurred to me that we could still be playing by those old rules, that Tina's presence here, after all these peacefuL years, could be due to anything but the wildest and most innocent coincidence. But the old stand-by signal meant business.

It meant: Wipe that silly look off your face, Buster, before you louse up the works. You don 't know me, you fool.

It meant that she was working again-perhaps, unlike me, she'd never stopped. It meant that she expected me to help her, after fifteen years.