In the series of my monothematic Calendar this year...
For me the role (or rather - roles) that Jang Dongyun had to play in Tale of Nokdu was one of the best and hardest to show this year. He had to switch between playing a guy and a woman without contrasting them to the point of being tasteless pastiche. OK, anyone can play a lovable lad, but having this lad to pretend to be a woman is not a simple cookie. It's easy for such a task to be turned into a slapstick comedy. It's easy to be over the top or disrespectful. Yes, Nokdu had its comedy gold moments but they did not stem from the "mistaken identity" trope of guys playing a caricature of a woman. Au contraire - Dongyun played Nokdu playing a woman with care and respect. Never once in the whole series he felt "reduced" for having to pretend to be a woman. That, and Dongyun being honestly curious about the make-up trailer, as Kim Sohyeon once revealed :)
The risky role may lead to be type cast as a pretty guy only. Well, he is ridiculously pretty but who knows, maybe he'll be a psycho killer soon on our screens?
Honorable mention:
Kim Namgil as Father Haeil. Given the current climate around the Catholic Church a series that makes a Catholic priest its main and likable character in something other than an exorcism expert, shows how much risk SBS actually took to make it work. And boy - DID IT WORK! Father Haeil (or Michael, aptly named after the Archangel known as the God's Sword) is a broken man finding (relative) solace in a priestly life - right until his friend, Father Gabriel is murdered.
And then all Hell breaks loose...