Lucy Liu, Jonny Lee Miller Lucy Liu, Jonny Lee Miller

Elementary's Sherlock Holmes is the best detective in the world, which means it shouldn't be long before he uncovers Watson's little secret: She's lying about her employment status so she can continue being his sober companion.

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Yes, Sherlock has come to realize how much he needs Watson, but has Watson come to see how much she actually needs him? "Her therapist asks her that point-blank," Doherty says. "The funny thing is that it's a question that won't actually make it to the episode, but there will be an interesting conversation about it and why she did it. I'd say the more important question is: What is Joan to Sherlock in the wake of that revelation?"

Elementary airs Thursdays at 10/9c on CBS.