I got through this book in about three sessions, desperate to find out what was going on. The plotting, the settings and most of the characters convinced, and for about two-thirds of the story, it would be difficult to fault it. Perhaps inevitably when the big revelation(s) start to happen in the last third, I thought there was a sense of a solution being constructed to explain the mystery, rather than the other way round. Some of the motivations, particularly of the "historical" characters, seemed forced or improbable. As to the biggest revelation of the lot, I THINK that McDevitt and Resnick had their tongues firmly in their (respective) cheeks when they devised it. A thumping good read, but not, ultimately, totally convincing. I've read everything McDevitt has written, but hadn't discovered Resnick - I'll certainly now start in on his books with every expectation of enjoying them.