In the new Taiwanese military drama Paradise In Service, Ethan Juan plays a soldier assigned to a brothel. As is to be expected, his character has an intimate scene with one of the women who work there.

But he did not strip for the sake of stripping, he said on Monday while in town to promote the movie.

"Actors have to serve the script. When you meet a director you trust, an acting partner who trusts you, and the story calls for it, then I wouldn't rule out such scenes. But it has to be under those conditions," said Juan, 31, looking spiffy in an all-black ensemble at a press conference held at ArtScience Museum at Marina Bay Sands.

Paradise In Service, directed by Doze Niu, opens here on Nov 6. Niu fell foul of authorities in Taiwan last year when shooting the film, after he was accused of attempting to smuggle a Chinese national on to a militarily sensitive site. He and Chinese cinematographer Cao Yu have been indicted for the offence and await further action from the authorities.

Set on the island of Kinmen from 1969 to 1972, the film is also about the soldiers who had to flee mainland China in the wake of the civil war and whose hearts always yearned for a home they could no longer return to.

Juan's reason for taking on the role is in fact quite personal.

He said: "It's the story of my grandfather's generation and I've heard him talk about it and seen so many old photographs. I wanted to narrow the distance between us and, through this film, better understand what he's thinking."

Like the soldiers in the film, Juan's grandfather also longed to return to China. It was a feeling Juan could not understand in the past.

He would say to the elder man: "I'm born in Taiwan and you've been in Taiwan for so many years, so why do you feel that way?"

After making the film, he realised: "It was the hope and pain of their lives. For us, returning home is a simple matter, but for them, it's a lifetime of waiting."