Park Shin Hye has disguised herself as a boy before. In "You're Beautiful" she played a girl who was pretending to be her twin brother so she could perform with a top band.

Her character temporarily fooled some of her fellow band members, even causing one some concern because he was attracted to her.

In the last six years Park has grown into a glamorous and sophisticated actress. But that has not stopped the 26-year-old actress from trying another male role. This time she plays a man in the film "Beauty Inside."

She's one of many actors who take turns playing the role of Woo Jin, a character who is a different person every time he wakes up. Some days he is old. Some days he is young. Some days he is a woman. Han Hyo Joo plays Lee Soo, the woman he loves. She remains the same and she has to contend with his changes. The film asks the question, what is it that you love about a person? Would it transcend the way they looked? Would you still love them if they were another gender?

Because she loves Woo Jin for the person he is inside, Han Hyo Joo's character gets to have a love line with several actors, including Park Sin Hye.

Park makes for a very handsome Woo Jin. In the film she is the fourth actor to play the character.

Altogether 21 actors play Woo Jin. They include Kim Dae Myung, Do Ji Han, Bae Sung Woo, Lee Bum Soo, Park Seo Joon, Kim Sang Ho, Chun Woo Hee, Ueuno Juri, Lee Jae Joon, Kim Min Jae, Lee Hyun Woo, Cho Dal Hwan, Lee Jin Woo, Hong Da Mi, Seo Kang Joon, Kim Hee Won, Lee Dong Wook, Go Ah Sung, Kim Joo Hyuk and Yoo Yeon Suk.

The actors faced the unusual challenge of needing to have their separate performances become a seamless whole. That meant they had to carefully study and evoke each other's performances.

"Beauty Inside" is one of four films that Park Shin Hye has done in the last two years. She also appeared in "Miracle in Cell No. 7," "One Perfect Day" and "The Royal Tailor."

Park debuted in dramas as a child actress, playing the young Choi Ji Woo in "Stairway to Heaven." Her most recent drama hits include 'The Heirs" with Lee Min Ho and "Pinocchio" with Lee Jong Suk.

"Beauty Inside" will be released on August 20.