Earlier the Saif Ali Khan - Kangana Ranaut pair was roped in for a romantic comedy (Mr. Chaalu) but the deal fell through. However, looks like, the two have bagged yet another movie where they will be sharing the screen space.

Based on the popular romantic thriller novel \'Devotion of Suspect X\', Balaji Motion Pictures have signed Kangana as the leading lady of the film.

The actress will play the role of a single mother who accidentally murders her abusive husband under the circumstance of self defense. A helpful neighbor, who is a genius mathematics professor, comes to their rescue and plots a foolproof conspiracy in order to protect the mother and daughter. However, an intelligent investigator is not convinced with the alibis and evidence presented in front of him and hires a smart physicist to solve the case. What follows is a chase between two equally clever and witty people and a climax that decides the victory of one.

Though we hear that Saif Ali Khan will play the investigator, the character details have not been divulged. Earlier we had also reported that Vidyut Jamval will also play a prominent role in the film. There are also rumours that Fawad Khan will be seen in the film but there has been no confirmation on the same.

Directed by Sujoy Gosh, the film is slated to go on floor in April and it is being said that it will be shot extensively in Kolkata.

Kangana Ranaut to now star opposite Saif Ali Khan in â€˜Devotion of Suspect Xâ€™