The “M” mystery is solved!

Thursday’s Elementary finally unmasked Sherlock’s biggest foe, Moriarty, and, turns out, it’s his one and only love Irene Adler (guest star Natalie Dormer)!

How’s that for a twist?

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Sherlock first catches on to her when he notices that one of her birthmarks is missing, but he suspects that she’s working for Moriarty, not that she is the Big Bad.

So why did she come after the consulting detective back in London? Because he interrupted several of her meticulously planned assassination plans. Her first instinct was to kill him discreetly, but then she became curious about Holmes’ mind. It was “something too beautiful and complicated to destroy.” Instead, she found a way to study him and became the American Irene Adler. (Moriarty, thankfully, lets Natalie Dormer keep her British accent.) She continued to let him live because she discovered that he was not the threat she imagined he was. When he spiraled into addiction following her “death,” he proved that he was inferior to her. Then she came to New York because she heard of his “miraculous recovery.” Irene admits all this to Sherlock, who counters that the real reason she’s here is because he’s getting close to another one of her plots.

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“I see games,” she replies. “You’re a game I’ll win every time.”

“I would never kill you,” she continues. “Not in a million years. You’re still a work of art. I appreciate art. What I will do is hurt you, worse than I did before. … So please, for your own good, let me win.”

So what’s the nature of her business in New York? She’s cooked up a scheme to start a major political kerfuffle between Macedonia and Greece that would keep the former out of the European Union and let her profit big time when the old currency skyrockets. Although Sherlock eventually figures it out, it’s too late. Three people die in the process, and Moriarty’s game takes its toll on the investigator.

Joan urges him to let her go. “It is the only way this does not eat you alive,” she pleads. “She was right. Let her win.”

Instead of heeding her warning, Sherlock steals some drugs and overdoses at home. In the hospital, Irene pays him a visit. “I didn’t want this. Not again,” she admits. “I want to help you.” In fact, she wants him to come to London with her. “You’re broken to pieces right now. I can put you back together. And once you’re whole, I can show you a different way to live.”

But it turns out Sherlock’s not the only person who can surprise Moriarty. Watson figured her out and realized the real reason she could never kill Holmes: They both made the mistake of falling in love and being stupid. Watson then encouraged her partner to make it look like Irene had won by faking an overdose and drawing her to the hospital, where the cops were waiting.

Case closed.

Elementary fans, hit the comments with your thoughts on the Moriarty twist and then grade the episode below.