 Why does Mr. Oyster want to hire Simon and Betty?
He looked over at Betty and said, almost as though reciting, "What I need is a vacation." "Providence," Simon told her whilst fiddling with the aspirin bottle, "will provide." Betty bounced up with Olympic agility and had the door swinging wide before the knocking was quite completed. Simon said unenthusiastically, "Good morning, Mr. Oyster." The client fussed himself with Betty's assistance into the seat, bug-eyed Simon, said finally, "You know my name, that's pretty good. "Then you'll realize that there are a dozen explanations of the paradoxes of time travel. It's my contention that within a century or so man will have solved the problems of immortality and eternal youth, and it's also my suspicion that he will eventually be able to travel in time. Simon seemed incapable of carrying the ball this morning, so Betty said, "But ... Mr. Oyster, if the future has developed time travel why don't we ever meet such travelers?" "The usual explanation, Betty, is that they can't afford to allow the space-time continuum track to be altered. Mr. Oyster went on. Mr. Oyster returned his glasses to their perch, bug-eyed Simon, but then nodded. Simon said, "You want to hire me to find a time traveler and in some manner or other—any manner will do—exhort from him the secret of eternal life and youth, which you figure the future will have discovered. Millions of liters of beer are put away, hundreds of thousands of barbecued chickens, a small herd of oxen are roasted whole over spits, millions of pair of weisswurst , a very special sausage, millions upon millions of pretzels—" "All right," Simon said. "No ma'am, you'd have to stick to some great event, both for the sake of actual interest and for protection against being unmasked." Mr. Oyster was taken aback himself. "A hundred dollars a day plus expenses," Mr. Oyster said quietly. It goes like this:" I got a thousand dollars from Mr. Oyster (Simon began) in the way of an advance, and leaving him with Betty who was making out a receipt, I hustled back to the apartment and packed a bag. It takes roughly seven and a half hours from Gander to Shannon and I spent that time dreaming up material I could put into my reports to Mr. Oyster.
 He thinks the time traveler will have the secret to never-ending youth.
 He thinks the time traveler will have the secret to never-ending youth.  He wants to know the secret of time travel and they are the best investigators around.  He wants to make sure his family's wealth continues in the future.  He wants to find out a secret for political reasons.