Mycroft enjoys his last few days in New York City trying to convince Sherlock to return back to London. When Sherlock doesn't budge he threatens that his father isn't happy that he hasn't returned to London, threatening that their father will take all his money away from Sherlock. When Sherlock reveals he can do it without his father, it is revealed that it was lie and Mycroft is planning something behind Sherlock's back.
When a young woman is stabbed to death it is revealed that she is the estranged daughter of billionaire computer genius Ian Gale. It is also revealed that Ian is hiding because he is dying. When Holmes and Watson track down the killer, Joan's knowledge of cardiology pays off when she discovers he was being slowly poisoned by his wife.