[I've been
reading]
The Lost Painting: The Quest for a Caravaggio Masterpiece

Random book from a library book sale and it was SO GOOD. This was all about figuring out which of many extant copies of an old painting may have been by the master Caravaggio. Lots of neat research and some great stories of the work behind the work. Harr turns it all into a fun to read story that has had more developments since this book was published.