This was the year when quite a few stars known for their gentle onscreen personalities tried playing tough guy roles.

Perhaps the most macho transformation of all was Kim Hyun Joong's. K-drama viewers first met him on the small screen as the sensitive, violin playing Yun Ji Hu in "Boys Over Flowers." While Ji Hu hung out with a mean crowd, he was the sensitive one. His character in "Playful Kiss" was not as nice but still had that same "pretty" look. Then came his role "Inspiring Generation."

To achieve the compact body of street fighter Shin Jung Tae, the singer-actor worked out for months, using training techniques from the era. His character is often bruised, cut and bleeding. He barely heals from one fight before he takes on a new challenge. And he's scarred emotionally as well. But fans seemed to relate to the new Kim Hyun Joong as well as they did to his softer side.

He may have learned a lesson from Lee Jun Ki. Lee played a motorcycle-riding bad guy who wasted much of his life in the action thriller "Two Weeks." He was first known for playing the effeminate clown who swayed a king in "The King and the Clown." The film was a huge success, catapulting him to instant stardom, but he became known for being a flower boy. His dramas did okay until he decided to break out of his pretty boy image by playing a violent NIS agent in "Time Between Dog and Wolf." In "Two Weeks" he again took a less than pretty role.

Park Yoochun's previous characters in dramas such as "Sungkyunkwan Scandal" and "Rooftop Prince" have relied on their charm. His character in "Missing You" was occasionally violent but also emotional and vulnerable. In "Three Days" he plays an agent tough enough to do whatever it takes to protect the president, even if that means killing friends and colleagues. Some viewers found it hard at first to accept the actor in a role that was so dispassionate. As the character's world began to unravel and he began to have doubts, he became much more relatable.

Even Lee Hongki and Daniel Choi went a shade meaner this year. While they are not playing thugs, both played uncharacteristic cold-hearted chaebols that are so unlike their previous roles. F.T. Island's Lee Hongki is known for playing likable characters, as is Daniel Choi.

While Lee Hongki's character softened up during the run of "Bride of the Century," there is no way to know what will happen to Daniel Choi's character during the run of his upcoming drama "Big Man."

Having flower boy good looks can boost an actor's career but it's also important to try a variety of roles so that you don't get stereotyped.