Game of Thrones S2E9-10: "Blackwater", "Valar Morghulis"
An absolutely perfect way to send off the second season. "Blackwater" is possibly the greatest television episode I've ever witnessed, and "Valar Morghulis" provides a perfect balance of denouement of the preceding events and set-up for what's still to come.
Can't wait to go through Season 3 again.