After creditably essaying seven looks in "7 Khoon Maaf" and 12 different characters in "What's Your Raashee?", Priyanka Chopra will be seen as a mentally-challenged girl in her upcoming film "Barfee", which she describes as "by far the most challenging role".

"I have started shooting for the film, have shot nearly five days till now. I must admit that it is quite a difficult task, " said Priyanka, who was here to unveil the wedding collection by jewellery brand Asmi for the ongoing The Great Indian Wedding Carnival.

"There is a very thin line between caricature and real. But surely, this role is by far the most challenging that I have come across, " added the 28-year-old who is reportedly spending time in a mental asylum to get into the skin of the character.

The film is being directed by Anurag Basu and it features Ranbir Kapoor as a deaf and dumb person, while Ileana D'Cruz is set to play a narrator.