Actress Kalki Koechlin, who essays the role of a cerebral palsy affected girl in Shonali Bose's directorial 'Margarita With A Straw', says the audition for this film was toughest for her and she took it as a test for herself.

"I loved the script. Shonali (Bose) e-mailed it to me and immediately I wrote back to her that I loved the script. It scared the hell out of me that she could even think that I could do this," Kalki said Wednesday at the trailer launch of the film, where Aamir Khan was present too.