She made her debut in Malayalam films. But she made her presence felt in Kollywood. Now she has set her sights on Bollywood. That is ambitious Nayanthara for you!This Christian girl from Kerala sure knows which side of the bread is buttered. And Nayan is going about realising her ambition with singular tenacity.Well, the latest on the starry-eyed siren is that she is all set to do a film in Bollywood. Noted director Ram Kumar Santoshi, says the grapevine, has offered her a role in his upcoming film. And needless to say, ambitious Thara has accepted the yet to be titled film with both hands!The buzz is that either Salman Khan or Hrithik Roshan will play the male lead. Meanwhile, Nayan is beavering away in Kollywood. She is doing Kalvanin Kathali with Surya. She is sizzling in an item number for Vijay's Sivakasi. Then there is the icing on the cake: Vettayadu Vilayadu with superstar Kamal Haasan !Now that she is Bollywood-bound, there is no stopping Nayan, it seems.