The drive back to Kahn’s condominium went faster than it had any right to. Lasoporp Rof was sulkily silent until they were actually inside and Kahn flicked on a light. “That is not fire. I’ve seen fire. It flickers.”

“It’s done with electrically heated wire.” When Kahn saw that meant nothing to the time traveler, he asked, “Well, what do your people use for artificial light?”

“Sun pills, of course,” was what he heard through Lasoporp Rof’s pangloss. It made no more sense to him than his explanation had to Lasoporp Rof.

He gave up. Waving the time traveler to his couch, he said, “Sit down, make yourself at home. Can I get you a beer-a cold, mildly alcoholic drink?” Kahn laughed at himself. He was starting to give definitions without even thinking about it.

“Yes, thank you.”

When the tech writer came back with two cans of Coors, he found Lasoporp Rof examining the Israeli-made menorah that decorated his coffee table. “What a strange coincidence,” the time traveler said, picking it up. “If you had one of these in my own time, I would think you were Jewish.”

“Very strange,” Kahn mumbled. With some reluctance, he let it go at that: it was either let go or spend the next three weeks asking questions.

He tamed on the television. Lasoporp Rof watched curiously as the screen lit up in bright colors and music came out of the speaker. It was a denture-adhesive commercial. Feeling his cheeks grow hot, Kahn was glad to get rid of it and turn on his VCR. The warning about unauthorized duplication at the front of the tape meant nothing to Lasoporp Rof, and this time the tech writer did not bother to explain.

Then the movie came on: a 1964 epic starring James Mason, Omar Sharif, Robert Morley, and a Telly Savalas who still had hair. Kahn realized the time traveler could not read the credits rolling across the screen. “It’s called Genghis Khan,” he said helpfully.

Lasoporp Rof almost jumped out of his furs and leathers. “This is a real record of his life?”

“No, a drama based on it. How could it be a real record, Lasoporp? We can’t travel in time.”

“First Primitive,” Lasoporp Rof said, as if reminding himself. That did not keep him from being a spellbound audience for the Far Eastern horse opera. Kahn had only seen parts of it on late-night TV. The knowledge of Mongol history his father had crammed down his unwilling throat made him wince at the inaccuracies, but Lasoporp Rof was plainly eating it up, battles, overwritten love scenes, and all.

When it was done, the time traveler said, “Let me see it again, so I am sure I have the sense impressions fixed in my memory. Together with the meal, it should give me enough material to keep my professors happy.”

Kahn blanched. Watching this two-hour turkey once had been bad; going through it twice came too close to cruel and unusual punishment. As he watched, he felt a twinge of guilt at what he was doing to far future historiography. He stifled it, but it made him wonder how much of what his father called historical fact was based on similarly trashy sources. A good bit, probably. He smiled, liking the idea.

At last the ordeal was over. Lasoporp Rof leaned over and kissed Kahn on both cheeks, then square on the mouth. “Thank you, T.G., thank you, thank you,” he said, and then he was gone, vanishing suddenly and silently as a popped soap bubble.

Kahn blinked and shook himself like a man emerging from a dream. He wondered if the evening had been just that, or an out-and-out hallucination. But his living room still reeked of rancid butter, there were beer cans on both ends of the coffee table, and never in his wildest nightmares would he have rented Genghis Khan. Besides, tomorrow morning the janitor would be asking him where his office window had gone. And there was that probability distortion stunt-He looked at his watch and saw to his surprise that it was only a little past ten. Thanks to Lasoporp Rof’s trick, he really had made good time on the road. He got out his address book, picked up the phone, and punched buttons. “Hello?”

“Jennifer? Hi, this is T.G. Feel like dinner and a movie Saturday?” He held his breath with the effort of bending the odds, then let it out in a disappointed gust as she said she was going to a party that night. That made the third time she’d told him no.

“-but I’d love to, the weekend after,” she finished. Kahn made the arrangements and hung up, feeling a bit like a world conqueror, after all.

In the course of research for an upcoming novel set in 1942, I read Albert Speer’s memoirs, and also some of those left behind by the Jews of the Warsaw ghetto. Combining Speer’s-and Hitler’s- grandiose vision of the Berlin that would rise after Germany won the war with the desperate reality of Jewish life under Nazi rule led to this story. Thank God it’s fiction.

Heinrich Gimpel glanced at the report on his desk to see again how many Reichsmarks the United States was being assessed for the Wehrmacht bases at New York, Chicago, and St. Louis. As he’d thought, the figures were up from those of 2009. Well, the Americans would pay-and in hard currency, too; none of their inflated dollars-or the panzer divisions would move out of those bases and collect what was owed the Germanic Empire. And if they collected some blood along with their pound of flesh, the prostrate United States was hardly in a position to complain.

Gimpel typed the new numbers into his computer, then saved the study on which he’d been working for the last couple of days. The Zeiss disk drive purred smoothly as it swallowed the data. He turned off the machine, then got up and put on his uniform greatcoat: in Berlin’s early March, winter still outblustered spring.

“Let’s call it a day, Heinrich,” Willi Dorsch said. Willi shared the office with Gimpel. He shook his head as he donned his greatcoat. “How long have you been here at Oberkommando der Wehrmacht now?”

“Going on twelve years,” Gimpel answered, buttoning buttons. “Why?”

His friend cheerfully sank the barb: “All that time at the high command, and a fancy uniform, and you still don’t look like a soldier.”

“I can’t help it,” Gimpel said; he knew too well that Willi was right. A tall, thin, balding man in his early forties, he had a tendency to shamble instead of parading, and wore his greatcoat as if it were cut from the English tweeds some professors still affected. He tried to set his high-crowned cap at a rakish angle, raised an eyebrow to get Dorsch’s reaction. Willi shook his head. Gimpel shrugged, spread his hands.

“I suppose I’ll just have to be martial for both of us,” Dorsch said. His cap gave him a fine dashing air. “Doing anything for dinner tonight?” The two men lived not far from each other.

“As a matter of fact, we are. I’m sorry. Lise invited a couple of friends over,” Gimpel said. “Let’s get together soon, though.”

“We’d better,” Dorsch said. “Erika’s saying she misses you again. Me, I’m getting jealous.”

“Oh, quatsch,” Gimpel said, using the pungent Berliner word for rubbish. “Maybe she needs her spectacles checked.” Willi was blond and ruddy and muscular, none of which desirable adjectives applied to Gimpel. “Or maybe it’s just my bridge game.”

Dorsch winced. “You know how to hurt a man, don’t you? Come on, let’s go.”

The wind outside the military headquarters had a bite to it. Gimpel shivered inside his overcoat. He pointed off to the left, toward the Great Hall.”The old-timers say the bulk of that thing has messed up our weather.”

“Old-timers always complain,” his friend answered. “That’s what makes them old-timers.” But Willi’s gaze followed Gimpel’s finger. He saw the Great Hall every day, but seldom really looked at it. “It’s big, all right, but is it big enough for that? I doubt it.” His voice, though, was doubtful, too.