2015 will be a hectic year for the Chote Nawab of Bollywood, Saif Ali Khan as he will be shooting for back to back three films in a row.

The 'Happy Ending' actor has almost finished with Kabir Khan's 'Phantom' and after this, he will move on to Reema Kagti's 'Mr. Chaalu'. And as if this much was not enough to keep the actor busy, buzz is that Saif has been roped in by director Sujoy Ghosh for his next.

In an adaptation of a Japanese thriller novel titled 'The Devotion of Suspect X', the actor is apparently playing a lead role. The story revolves around an intelligent mathematician and a single mother who is in desperate need of protecting her family and her daughter.

In a defensive move, when she ends up killing her abusive husband, it is her neighbour, the math teacher who comes to her rescue and devises a plot as a cover-up. However, the investigation is in the hands of a strong headed detective and he senses something amiss and decides to uncover the truth.

But the mystery deepens when the cop decides to get an equally intelligent doctor on board for the investigation, who co-incidentally is the batch mate of the math teacher.

Although there is no confirmation regarding the leading lady, Ekta Kapoor has bought the rights of the novel for the film.