Joseph Gordon-Levitt as Nightwing. OH WAIT THAT HASN'T HAPPENED YET

Seconding Cersei! Lena Headey s such a fabulous bitch. Additionally, Nikolaj Coster-Waldau as Jaime.

Matthew McConaughey in True Detective. Greatest acting I have ever seen in my life, second only to Heath Ledger's Joker, which was also an amazing casting decision.

James McAvoy as a young Professor Xavier. I just love him.

The entire cast of Sherlock.

Christoph Waltz as Colonel Hans Landa.

Mickey Rourke as Marv in Sin City. Love him.

Andrew Lincoln as Rick Grimes in The Walking Dead.

Amy Poehler as Leslie Knope in Parks and Rec.

Tatiana Maslany as Sarah Manning et al in Orphan Black.

Leonardo DiCaprio as Calvin Candie in Django Unchained. I think he's a flipfloppy actor who pulls in an equal amount of fantastic acting vs. mediocre acting. This was one case of phenomenal acting.

Ralph Fiennes as Monsieur Gustave H in The Grand Budapest Hotel, and also as Voldemort. Some people hate him as Voldy, I freaking love him to death.

In fact, I will just go so far as to say that the entire cast of Harry Potter was absolutely perfect, save for one person who I am going to name in the terrible casting thread instead.