Sherlock has found himself involved in a case against his will, with a mysterious person taking a hostage and forcing the detective to play a game to set her free. Sherlock and John headed to St Bart's Laboratory to examine the newly discovered trainers. The clue triggers a memory of Sherlock's, a tragic case from his childhood. Upon solving the case, the hostage is set free. Watson continues to liaise with Mycroft about missing missile plans, while Sherlock has already moved onto the second part of the game. A banker's car is found abandoned, and filled with bloodstains. Time is ticking for Sherlock and John, with six hours left until the hostage is in critical danger!