Marooned In Realtime By Vernor Vinge
Sometime in the near future humanity invents the "bobble", a device that generates a perfect stasis field, time does not pass inside at all. Totally impervious, Bobbies can be used as weapons, shielding, long-term storage, or as a one-way time machine into the future. Far into the future in an unpopulated Earth, a small collection of people who (for various reasons) have bobbled for immense amounts of time decide to collectively bobble again for 50 million years.
But one person is left behind, forcibly unable to bobble, effectively murdered as she lives out her natural life while every other living human is in stasis. 50 million years later, the others immediately realise that they have a murderer in their midst. Can old-school detective Wil Brierson crack the case?
Marooned in Realtime attempts that most tricky of feats - the hard science fiction murder mystery, and it comes pretty close to succeeding. The rules of the game (how the bobbles work, the various motivations and personal histories of the suspects, etc) are well laid out and the book never feels dull, almost an action thriller rather than a detective story.
I completely missed the clues that pointed to the murder, the solution hinges on a rather subtle point. But by that stage it didn't matter because the story has widened in unexpected ways as the full implications of what the characters have discovered about the world and each other becomes clearer. Mystery, action, spaceships, aquatic monkeys, evolved dogs, what more do you people want?
Highly recommended if you like this sort of thing.