This is the first book in a series called The Dresden Files, about a wizard who investigates paranormal crimes. It was recommended to me by a librarian, and I quite enjoyed it.
The wizard is called Harry Blackstone Copperfield Dresden, and he’s got a lot of baggage − he has killed a few people in his time, had some uncomfortable interactions with black magic, and has a pretty crappy love life. In this book, he’s out on two weird cases: in one, people are dying by having their hearts explode, and in the other, a guy who is sort of into magic disappears and his wife wants him found. The Chicago mob gets involved, and also demons, and a skull that contains a spirit who knows all about potions. It’s a little bit all over the place, but it’s totally fun. I’ve got the next book in the series lined up on my shelf.