When a young girl goes missing, Watson puts his mid-life crisis to one side and helps Holmes try to find her. Dealing with the sceptical police, a bunch of teenagers and a grumpy step-father all add to the challenges of the case. Can Holmes find her before it is too late? And before Detective Chief Inspector Gregson makes the mistake of his career? And will Watson achieve that illusive book-deal he's dreaming of? A modern re-working of Sir Arthur Conan Doyle's original Sherlock Holmes adventure, A Case of Identity. The fourth story in a series of five.