Secrets of Life and Death

Mediocre urban fantasy about people rescued from death only to be turned into revenants. Our heroes in the present day include a couple such revenants, and a university professor. They face an adversary whose roots lie in the late 16th century, which we learn by following the exploits of John Dee and Edward Kelley (actual historical figures) in Poland of that time. But all the historical stuff feels superfluous to the main story and could have been boiled down from half the book to a couple of chapters. There's plenty of magic in the story, with little framework governing how it works, so it feels rather arbitrary. The book does have some suspenseful sequences, but overall I found it not very engaging,