Island of the Mad

One of the Mary Russell and Sherlock Holmes series by Laurie R. King. I love this series! I'm this one, Russell and Holmes help an old friend track down a missing, and aunt. Lady Vivian Beaconsfield has spent most of her adult life in one asylum or another since the loss of her brother and father in the Great War. Her mental state seemed to be improving, but she's now disappeared after an outing from Bethlem Royal Hospital (better known as Bedlam). Together, Russell and Holmes search Bedlam to Venice, only to find the increasing shadow of Benito Mussolini.