While recovering from his gun shot wounds, Holmes eschews painkillers while working on a case of a Greek shipping magnate - involving an assassination and currency manipulation - before his final showdown with Moriarty.
- "Elementary"- "Heroine" - May 16, 2013
So, there you have it, Irene Adler is actually Moriarty and she's got a gun pointed at Sherlock.
As he lies on the ground writhing from the gunshot wound to his shoulder she monologues about how she seduced him, toyed with him, studied him, was annoyed by him because his work with Scotland Yard was messing up several of her assassination plans, fascinated by him because he was so brilliant, but not as brilliant as she is. She won't kill him because she considers him a work of art and she loves art and says he's not the threat she expected him to be, proved by his drug addiction. He believes that she thinks he's close to undermining one of her plots again. She tells him simply to let her win. And if he doesn't he will hurt him, worse than she has before. She leaves.
Watson returns home and he fills her in as she removes the bullet and stitches him up. She says he needs painkillers, the non-addictive kind. He thinks the pain gives him clarity. He also says the truth has been liberating.
Through a series of clues they deduce that Irene/Moriarty is in town to make sure a Greek national named Theophilus kills the ruler of Macedonia's son. If she achieves this goal she will make a billion dollars thanks to an investment in Macedonian currency. (Macedonia is set to join the EU and begin using the Euro. But if a famous Greek national commits this murder than there will be an uproar that will likely mean they won't join the EU.)
Gregson is worried that an injured, devastated Holmes should be benched from the investigation. Watson says to give him some slack and she'll let him know when he needs to be stopped.
Irene/Moriarty tricks Watson into thinking her mother is in the hospital and strong arms her into a meeting. She's curious to know why Holmes is interested in Watson, how she fits in his life. Watson gives her nothing but awesome attitude.
They trail the Greek national, discover that Irene/Moriarty has kidnapped his daughter and this is how she is going to get him to commit the murder. They figure this all out as Theophilus is heading to kill the Macedonian ruler. They are too late, the ruler's bodyguard is working for Irene/Moriarty. He kills the leader and his wife and the bodyguard kills Theophilus.
When they interrogate the bodyguard he refuses to cop to anything regarding Irene/Moriarty. Sherlock freaks out they fight and Watson talks him off the ledge. She tells him to "let her win."
Sherlock ditches his security and finally arrives home. He tells Bell that he's going to take a shower. Bell gets a call that a drug dealer was beaten and robbed by a British man near Sherlock's home. Worried that he's relapsed Bell busts the door down. Sherlock is lying on the floor, passed out, a syringe lying nearby. He has overdosed.
Irene/Moriarty comes to visit him in the hospital and gloat and then offers him a chance to run away with her and live a life he could never have dreamed of. He said they both made the same mistake, they fell in love and it made them stupid. And then he lowers the boom. Watson "solved" Moriarty. The whole overdose was a charade. They knew she would come to the hospital. They set the trap and she fell into it. Watson and Gregson enter the room and bust her. Her billion dollar windfall has been frozen.
Back on the roof of the apartment Holmes shows Watson something incredible. The bee in the box he received early in the year that was totally unique was not supposed to be able to breed with other kinds of bees. But Holmes added the bee to his bee colony on the roof and, lo and behold, it bred. He shows her the birth of the first offspring with a magnifying glass. It has to be classified as an entirely new species and he gets to name it and he's calling it "Euglassia Watsonia." Awww, he named the bee after her. She sits and watches as more bees are born.