Part of the reason we IMDb reviewers get the big bucks -- not to mention the X-Mas party -- is that we are privileged to be be able to look at an episode and then place it in the multi-tiered hierarchy of TV history.
Usually that is not much of challenge but this episode was a game changer. To this point the JJ had the comfy feel of an old Bogey film, private eye, wisecracks, interesting characters, etc. To be honest, I could have watch THAT show for 50 or 60 episodes.
But twas not to be. Instead in this episode the Kilgrave arc, which was really secondary until now, goes front and center and full metal jacket. Not only is this one of the most incredible mid-season transitions I have ever seen but the only analog I can find is Sir Tony Hopkins playing Hannibal Lector in Silence of the Lambs. To evoke sympathy for a villain is not merely tricky, it is often impossible. But this episode, backed by great writing and great acting, pulls it off.
Gob smacked.