After a teaser that reveals Sherlock tied up in the back of an SUV, we flash back to two days earlier when Gregson calls him in to consult on a case. A Wall Street executive has gone missing, and even though Holmes despises finance types, he is still eager to solve the mystery. Sherlock uncovers the executive's shady dealings and finds that he died of an apparent heroin overdose. But even though the police have all but ruled out foul play, Holmes suspects that someone at the victim's firm may be killing his way to the top.