I'm not giving anything away by telling you that the Fourth Crusade is the one where the crusaders sack and loot a series of Christian cities, most famously Constantinople (capital of Byzantium). Knowing that, you might expect this book to be depressing. It's actually highly entertaining--a "rip-roaring adventure yarn" (tm)--with lots of action, suspense, and humor. It is, in fact, very like an extended, well-plotted D&D campaign, or better, module with pre-gen characters thrown together in a contrived situation and sent On a Quest. The two protagonists are a bard/assassin and a paladin. Watch them not get along! and then learn to appreciate one another! There's another rogue, a fighter, a tyrant or two, some spineless clerics, and a kickass woman posing as an Arab princess who is rescued by the party (I mean, the main characters). Still, there is character development here. ANd the history is pretty accurate, tho it's the My-Characters-Made-EVERYTHING-Happen school of historical fiction. Essentially, this is shallow fun that's well paced and won't leave you with a toothache.