/> Irrfan Khan who's currently shooting for English director Danny Boyle's much talked-about Slumdog Millionaire in Mumbai, says he enjoyed his second film with Arshad Warsi.

"Sunday was fun, though I can't say the same about the first film that we did together. I didn't enjoy doing Chocolate. Till the end we weren't told what the story was and the plot kept getting changed all the time.

On the other hand during Sunday director Rohit Shetty was very rigid about going by the plot. But Arshad and I were constantly given a chance to improvise.

We had loads of fun because I like working with competent actors.And Arshad is outstanding. In fact Arshad and I have a third film Krazzy 4 lined up. In it we're both wacked-out and again, constantly together."

Irrfan is looking forward to more films with Arshad. Things are looking upbeat for the actor who turned a year older in January,

"Birthdays are no big deal in our home. We treat it like any ordinary day. What matters is not the age but the density of the work that we do.

In Danny Boyle's Slumdog Millionaire I'm the narrator, catalyst and obstacle to the protagonist's progression. I play a cop. But I've no name. I'll be billed 'The Cop' in the film which releases at the end of the year."

Irrfan says he was keen to work with Danny Boyle. "I've been a fan of his films for a long time. I've seen them all. When I got to know he was making a film with Indian actors it was important for me to just be part of the project.

I have about 14-15 days' work in Slumdog Millionaire and I've enjoyed every bit of it."

This would be Irrfan's third major international venture in a year after Mira Nair's The Namesake and Michael Winterbottom's A Mighty Heart."

Says Irrfan, "I don't look at Slumdog Millionaire as another opportunity to make a mark abroad. For me every challenge as an actor is equally satisfying.

What I look forward to is the chance to work with good actors, whether it's Arshad Warsi in Sunday and Krazzy 4 or young Dev Patel who plays the hero in Slumdog Millionaire.

He's a very charming Indian from Britain. Sharing screen space with new actors whether it's Angelina Jolie or Dev Patel, is always a pleasure."