When asked what his favorite scene was in "You Who Came From The Stars," Kim Soo Hyun singled out a kissing scene.

"The frozen-in-time kiss scene on the frozen lake," he said at a recent press conference. "It snowed a lot and it was very cold but the scene was good at showing the warm emotions."

The actor put a lot of thought into how he should act out the kiss scenes, wondering how experienced Do Min Joon should appear. The attractive alien had been on the earth for 400 years but he never really had much opportunity to kiss anyone as a kiss could make him physically sick.

"I thought that Do Min Joon should be stiff and awkward but at staff meetings we talked about how we wanted viewers to respond to the kiss scenes, so I focused instead on creating better angles."

He and Jun Ji Hyun were comfortable working together because they previously acted together in the film "The Thieves." He thought that she was perfect for the role of Chun Song Yi. As soon as he read the script, he was taken with the character, that he described as cute and lovable.

"Jun Ji Hyun's personality is very cheerful in real life and she makes it easy for me to focus on the romantic feelings," he said. "I was very focused.

The film's production crew was happy to be working with the actress too so the mood on set was always upbeat. She is known for being professional and considerate.

"Ji Hyun noona always prepares well before coming on set so she was always the best Chun Song Yi," he said.

To create a realistic character, Kim Soo Hyun tried to make the alien Do Min Joon seem more human. Rather than think of him as an alien, he perceived him as someone who had suffered a lot during the time he spent on earth, someone whose emotional scars kept him from getting involved with people.

Fans of the show will say that he did a good job of touching viewers' hearts with his portrayal. But then he has succeeded in doing that with his previous dramas too. "The Moon Embracing The Sun" was also a ratings hit.

As to "You Who Came From The Stars," the actor says it was a success in large part due to the writing.

"They were very attractive characters to begin with," he said. "And that allowed viewers to open their hearts."