Can Sherlock and Lucy outwit a seacoast spy, or will they be swept away by the undercurrents of espionage? Cornwall, 1901: Lucy and Jack, in the guise of a tranquil honeymoon, track a spy who threatens England's vital global telegraph lines. Enter Holmes and Watson, with young Irregulars Becky and Flynn in tow, diving into a whirlpool of sunken treasure and spectral sirens. As cryptic messages, hidden loot, and the song of a Cornwall siren entwine,...