THIS, this is how create amazing TV. Agents of Shield have been improving every season and by the looks of things the show will take yet another step. I very seldom hand out 10s, only done so for 5 times before from what I remember, but this deserve it!
To me AoS is the best superhero show ever made. There are a couple of DC animated shows that have almost been on this level but for regular TV I can only remember a few episodes of Smallville and the first two season of Arrow that has even come close to the fantastic show that is Agents of Shield.
This episode is almost confusing. I kept saying "what!?" and "What the hella is going on!?" all the time, but in a very, very good way. The episode feels like a great x-files or a Twilight Zone episode, with some Alien thrown in there. The cast is amazing and the sort of clunky feel from the acting/script that existed during the first season, and occasionally later, is now completely gone, the directing great and everything just scream high quality and intelligence.
If you want amazing TV entertainment this is the show for you. AoS is the best Sci-fi since Fringe, best group of characters since Firefly, and the best darn superhero show ever made.