Salman Khan was the original choice for Bajirao, and since Aishwarya Rai Bachchan had resolved not to work with him, the female lead chosen in Bajirao Mastani was Kareena Kapoor Khan.
The two Khans, Kareena and Salman had done a smashing photoshoot together and were all set to go on the floors with what promised to be the best film of their career, when Salman did the unthinkable: he offered Priyadarshan a chance to direct Salman and Kareena ahead of Bajirao Mastani, and that too for Kyon Ki a nonsensical adaptation of One Flew Over The Cuckoo’s Nest.
Why did Salman Khan abort his own epic project? Some say this was his revenge on Bhansali for not having cast Katrina Kaif as Mastani. At that point of time, Salman was heavily recommending Katrina to filmmakers. Bhansali refused to cast her.
Bajirao Mastani was then put on the backburner. Bhansali instead made Guzaarish with Aishwarya and Hrithik Roshan.
Many years later Bajirao Mastani was revived. Bajirao’s role was offered to Ajay Devgn, Shah Rukh Khan and Hrithik Roshan, all of whom had their own reasons for turning down the part.
Finally the film was made with Ranveer Singh and Deepika Padukone in the eponymous parts. The rest was history, in more ways than one.