Akshay will play one of the leads in the two-hero movie, the shooting of which is scheduled to start early next year. The other male lead will be announced next week.
"I can't divulge too much now. But what I can definitely say is that the movie is mainstream and has a very strong underlying social message. It is solid and hard hitting. Punit brought me this amazing script. I immediately approached Akshay and he was equally thrilled with the idea," Karan said in a statement.
Talking about Akshay, Johar said, "If Dharma Productions has to collaborate with Akshay, then it has to be the right kind of film. And, as I said earlier, this one, apart from being commercial, has a strong voice."
On the collaboration, Akshay said, "We are two very passionate producers with one great aim -- to entertain. Both Karan and I want to make our fathers proud."
Karan's mother Hiroo Johar and Akshay's wife Twinkle Khanna will co-produce the film.
Before the film with Akshay kick starts, Punit will direct Imran Khan and Kareena Kapoor in a love story titled Gori Tere Pyar Mein, which goes on floors in March.
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