Legion by Brandon Sanderson

This book is about a supposedly sane man, Stephen Leeds, who is surrounded by multiple personalities with extraordinary skills. Leeds and his team of aspects are called in to find the inventor of a camera which can take photographs of the past. There's a little bit of adventure and a lot of speculation in this story. I enjoyed it, and I have a feeling there's more to it--or rather more to the character Leeds, who has a mysterious woman who disappeared in his past. Unless you're a big Sanderson fan or entirely opposed to e-books, I'd recommend the e-book rather than the print version: the novella size seems more reasonably priced digitally than in hard copy.