Watson begins to have second thoughts about leaving Holmes on Elementary. "M" is the 11th episode of the show's first season.
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Elementary Season 1 Episode 12 Quotes

Joan: [To Sherlock] I'm going to miss this, working with you. I think what you do is amazing.
Later On...
Sherlock: [To Joan] I'm going to miss this, working with you. I think what you do is amazing.

Joan: I like what I do right now.
Therapist: Your right now, is coming to an end.