The book is set in the future, on the campus of a large university on Earth. The main character is a professor who discovers he was duplicated in a teleportation accident, but that his duplicate has since died in an accident while he (the original) was off-planet. So he’s officially dead—out of a job—and something of an embarrassment to the school administration.
And all this is set against a bizarre background. Time travel has been developed—in fact, William Shakespeare is on campus to give a lecture about how he didn’t really write his plays. Also, creatures such as goblins, faeries, trolls and banshees have turned out to really exist and turn out to play an important role in the ensuing shenanigans. There’s a crystal planet out there somewhere—a survivor from a previous universe--containing something like 50 billion years worth of knowledge that is now for sale. There are some rather icky aliens (hive minds whose wheeled-limbed bodies are full of writhing insects) who may or may not be mankind’s deadly enemy. There’s a series of paintings by a pre-time travel era artist that nonetheless seem to be eyewitness scenes from the Jurassic Era.
Our hero, along with his best friends (a ghost who doesn’t remember who he was when he was alive, a highly educated Neanderthal, and a young woman with a pet bio-mechanical saber-toothed tiger) has to make sense of everything. But they have to deal with potentially dangerous aliens, greedy humans, stubborn administrators, cash-strapped department heads and trolls who are ticked off because the goblins won’t share the latest batch of ale with them.
And, yes, all this does tie together at the end. But I don’t want to even hint how. Check your library or used-book dealers to dig up a copy and find out for yourself.