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glasses. McGavin perched his bottom on the edge of the granite desk and faced Don and Sarah. He was not a particularly good-looking man, thought Don. He had doughy features and a small, receding chin that made his already large forehead seem even bigger. Still, he'd doubtless had some cosmetic work done. Don knew he was sixty-something, but he didn't look a day over twenty-five.
    The robot was suddenly there, handing Don a beautiful crystal tumbler full of water, with two ice cubes bobbing in it. The machine handed a similar glass to Sarah, and one to McGavin, and then silently withdrew to behind the bar.
    "Now," said McGavin, "let's talk turkey. I said I've got a"—he paused, and gave the word a special weight, recalling the banter of the day before—" proposition for you." He was looking at Sarah exclusively, Don noted. "And I do."
    Sarah smiled. "As we used to say about the Very Large Array, I'm all ears."
    McGavin nodded. "The first message we got from Sig Drac was a real poser, until you figured out its purpose. And this one is even more of a puzzle, it seems. Encrypted! Who'd have guessed?"
    "It's baffling," she agreed.
    "That it is," said McGavin. "That it is. But I'm sure you can help us crack it."
    "I'm no expert in decryption or codes, or things like that," she said. "My expertise, if I have any, is in exactly the opposite: understanding things that were designed to be read by anyone."
    "Granted, granted. But you had such insight into what the Dracons were getting at last time. And we know how to decrypt the current message. I'm told the aliens made the technique very clear. All we have to do is figure out what the decryption key is, and I suspect your skill is going to be valuable there."
    "You're very kind," she said, "but—"
    "No, really," said McGavin. "You were a crucial part of it then, I'm sure you're going to be a crucial part of it now, and you'll continue to be so well into the future."
    She blinked. "The future?"
    "Yes, yes, the future. We've got a dialogue going here, and we need continuity . I'm sure we'll unlock the current message, and, even if we don't, we'll still send a response. And I want you to be around when the reply to that response arrives."
    Don felt his eyes narrowing, but Sarah just laughed. "Don't be silly. I'll be dead long before then."
    "Not necessarily," said McGavin.
    "It'll be thirty-eight years, minimum, before we get a reply to anything we send today," she said.
    "That's right," replied McGavin, his tone even.
    "And I'd be—well, um..."
    "A hundred and twenty-five," McGavin supplied.
    Don had had enough. "Mr. McGavin, don't be cruel. My wife and I have only a few years left, at best. We both know that."
    Sarah had drained her water glass. The robot silently appeared with a replacement and swapped it for the empty one.
    McGavin looked at Don. "The press has had it all wrong, you know, from day one. Most of the SETI community hasn't understood, either. This isn't a case of Earth talking to the second planet of the star Sigma Draconis. Planets don't talk to each other. People do. Some specific person on Sigma Draconis II sent the message, and one specific person on this planet—you, Dr. Sarah Halifax—figured out what he'd asked for, and organized our reply. The rest of us—all the humans here, and anyone else on Sigma Draconis who is curious about what's being said—have been reading over your shoulders. You've got a pen pal, Dr. Halifax. It happens that I, not you, pay the postage, but he's your pen pal."
    Sarah looked at Don, then back at McGavin. She took another sip of her water, perhaps to buy herself a few seconds to think. "That's an ... unusual interpretation," she said. "Because of the long times between sending messages and receiving replies, SETI is something whole civilizations do, not individuals."
    "No, no, that's not right at all," said McGavin. "Look, what are the fundamental tenets of SETI? Certainly one of them is this: almost any race we contact will be