Sherlock is tasked with locating a nobleman's missing son and seeks the assistance of William to gain entry into the nobleman's club. As they unravel the mystery, they find themselves entangled in a dangerous situation when a hostage taker, known for enjoying games, challenges them to a deadly game of Russian roulette. In a series of short tales, Bond imparts acting lessons to the Whitechapel troupe, Jack faces a daunting trial as he mentors three brothers, and Sherlock encounters a peculiar holiday case orchestrated by his brother, Mycroft.