After a commercial, we get caught up. Gale got a heart transplant a few weeks ago, but his body's rejecting it. He claims, "I'm too much of a fighter for my own good." Good one, dude. Watson notes that he has a very rare blood type that requires a family member for transfusions, which might explain what his daughter is doing in town. His daughter isn't in his biography, which is because she was the result of a one-night-stand in the mid-1980s. He paid her mother two million dollars to disappear. Natalie claims that Haley volunteered to donate blood when she found out that Ian Gale was sick. But his sickness was supposed to be a secret, as was his daughter. They brought her into town when he got sick because he felt that reconciling would be a good idea. Ian promises to give any help he can as long as they find whoever killed his daughter.
Police station. Gregson says there's one set of fingerprints from Haley's apartment that don't match anyone. Watson says there were no signs of a break-in, so maybe it was someone Haley knew. Holmes wants to go to the morgue to see if the police missed something on Haley's body, but Watson wants to cover that while he has dinner with Mycroft. Holmes rants about "the ritualization-slash-infantilization of eating" but Watson has no sympathy for him.
Morgue. The stab wound severed the abdominal aorta with great precision, so the doctor thinks it was someone who knew what they were doing. Bell brings in Maureen Tyler, Haley's mother. Bell verifies that she wants to do this, then he reveals Haley's face. Maureen's last discussion with Haley was an argument because she was upset to learn that Ian Gale was her father. Ian only cared about his daughter when he needed her, but Maureen didn't try to stop her from giving blood. She just didn't want her going to New York because she knew it would end badly. She says, "I know exactly who killed her." And then we don't find out what she says! What a rip-off.
The Diogenes. Sherlock admits that the dinner was exquisite and takes out his phone. Mycroft gives him the keys to 221B. He's had his stuff moved out, so now it's available to Sherlock again. Sherlock says he lives in New York now, possibly permanently. Mycroft doesn't buy it, because London was Sherlock's passion. And "father" is quite perturbed that Sherlock is still in America. Sherlock sighs, "Early onset dementia is so sad." Mycroft warns Sherlock that father might cut him off and evict him. He has discretionary control over the trust fund that Sherlock uses to pay Watson. Sherlock doesn't blink at this, because he's willing to live in a cardboard box if necessary. Mycroft tries to get him to worry about how his decision might affect Watson.