They played friends in the film "Twenty" and as a result of making the film Kim Woo Bin, Kang Ha Neul and 2PM's Junho have become the best of friends.

The film, which focuses on the love life of three 20-something men, was released on March 12. At the film's press conference the actors spoke about how they happened to form a lasting friendship.

"I gained two good friends from the film, Kim Woo Bin and Junho," said Kang Ha Neul. "I'm thankful for those guys and I want to stay together with them until the end. I feel like I have two new brothers."

The fun they had while filming made it easy for the actors to grow closer. Not only did the actors have to appear in many scenes together but the funny script and all the improvisation they did meant that they spent a lot of time laughing.

"There was a lot of freedom during the filming, and the staff made everyone feel so comfortable that all scenes in the movie had at least one ad-lib," said Kim Woo Bin.

Cracking up at the jokes made for a lot of bloopers but it also made shooting the film fun.

"If you converted the three months of our filming into 24 hours, we were laughing for 22 of those hours," said Kim.

He described it as a happy experience.

"There were a lot of scenes where we were able to support each other and the times when all three of us were together were a blast," said Kim. "We were all so happy."

The scenes they shot alone may have been easier but that does not mean they were as enjoyable.

"We didn't have the support and so it was a lot less fun," said Kim.

It was hard not to laugh. Even when they were not acting out a funny part of the script, they would joke around.

"We'd crack each other up with the most random jokes," said Junho. "We were lucky enough to be able to act with people our own age. So, we could just act naturally without holding anything back."

One night the actors decided to go out for a drink and declare their undying friendship.

"After we wrapped up filming one night when we were on a shoot in the countryside, when everyone was asleep, the 'Twenty' team got a little drunk and hollered 'I love you!' really loudly," said Kang Ha Neul.