Rain, 24, the song and dance sensation who has taken Asia by storm and landed on Time magazine's list of the world's 100 most influential people, stars in the quirky comedy called "I'm a Cyborg, But That's OK," which opened this week in South Korea.
The man who has sold millions of records across Asia, and performed in sold-out concerts at New York's Madison Garden, has traded his trademark trendy clothing for an awkward hospital gown in the film, where he plays a patient at a psychiatric ward alongside a character who thinks she is a robot.
"The main actress and myself spend a lot of time feeling rather disoriented," Rain, also known as Jeong Ji-hoon, told reporters earlier this week.
"The movie was a nice change of pace for me."
Rain's character tries to steal the identities of other patients at the hospital. The supposed cyborg played by actress Lim Soo-jung ends up stealing his heart.
The movie is directed by Park Chan-wook, whose film "Oldboy" won the Grand Prix at the Cannes Film Festival in 2004.
Park, known for his intricate story lines and dark humor was looking for lighter fare after completing his last movie "Sympathy for Lady Vengeance," which tells of a woman wrongly imprisoned, who once freed, seeks devastating revenge.
But some of the world's top music talents have a hard time dealing with celluloid. Critics bashed Britney Spears for her role in the flop "Crossroads" and Mariah Carey was about as sparkling as coal in her film "Glitter."
Rain, who glides and gyrates smoothly on the dance floor, said he often fumbled on the movie set.
"It was difficult delivering my lines while I was acting and finding the right time to take a breath," he said.
This isn't the first time Rain faces the camera. He has appeared -- perfectly at ease -- in three TV series in South Korea and is one of the country's top pitchmen in TV ads.
Although little known outside of Asia, Rain is a pop sensation at home and in major regional markets including Japan, China and Taiwan, where fans can't get enough of his dance-infused pop tunes.
Rain's fourth album came out earlier this year and he will embark on one of the largest tours for an Asian pop star this month. He will play in about a dozen countries over the next six months and his promoters expect ticket sales to total 100 billion won ($108.7 million).
A few Asian music stars have made inroads in international markets such as the United States but Rain believes the day will come when an artist from Asia will be as popular as Britney and Mariah are in around the world.
Rain sold out New York's Madison Square Garden for a show in February 2006.
"The U.S. market will start to love Asian artists as time goes by," he said.
(With additional reporting by Jang Sera)
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