time-traveling tourists and tour guides is a set-up that immediately reminds me of one of my favorite novels ever--Up The Line, by Robert Silverberg--but this one seems like it's going to be less bawdy and irreverent. however, it's early-going with this one, so I may yet be shocked and appalled by weird time-travel sex stuff. other than that...a great start, and I'm anxious to pick this up again later today. someone from the tour group visiting the early 21st century has gone missing off the bus, shortly after the bus had a minor collision that the tourists knew was part of the future and were looking forward to, as a bonus. it's the "person missing" part that has the tour guide upset, and since I've read Up The Line, I can't say I blame him, because it's after that when things tend to go horribly awry.