Actor Kim Bum at press call for the action TV drama "Hidden Identity" in Seoul, Wednesday. (OSEN)

Korean actor Kim Bum looks, well, different.

The star, who has been admired for his charming appearance, lost 14 kilograms and now sports a moustache.

Kim drastically lost weight for an upcoming TV action thriller series, "Hidden Identity."

"Since my character is cold-hearted, I lost 14 kilograms to match with my physical appearance," said Kim at a press conference Wednesday. "I had already put on weight, so I lost weight to appear more agile."

Kim's character, Cha Geon-woo, is traumatized by his lover's death and makes a decision to transform himself into a cold-blooded human killing machine.

(OSEN)

"To understand my character's traumatic past, I observed animals' motions and visited zoos and animal factories," said Kim. "Cha Geon-woo's nickname is 'rabid dog detective' and I saw a lot of dogs and (other) animals."

TV drama "Hidden Identity" follows a top-secret, special investigation team of five members -- including Kim and other actors Park Sung-woong, Yoon So-yi and Won-jong Lee -- launched by government police. The private agents pretend to lead normal lives while fighting crime undercover.

"Hidden Identity" will start broadcasting every Monday and Tuesday evening on MBC from June 16.

By Yoon Sarah (sarah356@heraldcorp.com)

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