Modern technology meets the classic detective story in this children's mystery series from Tracy Barrett, bestselling author of Anna of Byzantium. Xena and Xander Holmes think living in London will be boring. But one afternoon they’re handed a cryptic note that leads them to a hidden room—and a secret society. When they discover they’re related to Sherlock Holmes and inherit his unsolved casebook, life becomes so much more exciting. Can two smart kids with modern technology solve cases their famous ancestor couldn't?