Anurag Kashyap and Karan Johar
Anurag has always been very blunt in his opinions. The problem started when he started criticising Karan Johar and Yash Chopra's films.
Karan retorted that Anurag had lost his head and needed to get treatment.
But by the end of the year, the two directors patched up. Last heard, Anurag was roped in to write dialogues for Karan's next.