“That’s better.” Jack Breton relaxed a little further. “Do you mind if I sit down?”

“Go ahead. Do you mind if I have a drink?”

“Be my guest.” Jack uttered the words naturally and easily, turning their significance over in his mind. John had been his guest for nine years, as no man had ever been another’s guest before — but all that was coming to an end. When they both were seated he leaned forward in the big chair, making his voice cool, calm and reasonable. A lot depended on how he went about the task of making the unbelievable seem believable.

“How do you feel about time travel, John?”

John Breton sipped his drink. “I feel it’s impossible. Nobody could travel forward in time to here and now, because if present-day technology couldn’t envisage a time machine, nobody in the past could have built one. And nobody could travel back from the future to the present, because the past is unalterable. That’s how I feel about time travel.”

“How about in the other direction?”

“What other direction?”

“Straight across — at right angles to the two directions you’ve mentioned.”

“Oh, that.” John Breton took another drink, almost seeming to be enjoying himself. “When I was reading science fiction we didn’t really class that as honest-to-God time travel. That’s probability travel.”

“All right,” Jack said placatingly. “How do you feel about probability travel?”

“Are you telling me you’re from another present? From another time-stream?”

“Yes, John.”

“But, why? If it were true, what would bring you here?” John Breton raised the glass to his lips, but did not drink. His eyes were thoughtful. “Nine years, you said. Is it anything to do with…?”

“I heard voices, John.” Kate was standing in the doorway. “Who have you got with you? Oh…”

Jack Breton stood up as she entered the room, and the sight of her filled his eyes, just as it had on the last night he had seen her alive, until her image swamped his awareness — three-dftnensional, glowing, perfect. Kate’s gaze met his for an instant, then darted away again, and a single star-shell of pleasure burst in his head.