This book plays pinball with your head, specifically your suspension of disbelief. Usually an author will let you know up front what's true and what's false in his story, which characters are lying and their motivation - but those are the very things that create the mystery in this book. The characters, especially the sympathetic protagonist, want to believe their own fictions so much that you want to believe them too. But their stories clash, there's only one truth, and it turns out each of them has a part of it but not the whole. This makes for a real mind-bending uncertainty, especially in the last half of the book. The result is an unsettling and intriguing reading experience. Clarke has done something unique (to me, at least) in his story, something that made me think closely about the usually trustworthy relationship between an author and his reader. This book is twisty, sometimes confusing, but always fascinating.