Suyambulingam (Kamal Haasan), is shown watching a musical number from the movie Tamil movie Siraichalai, featuring Mohan Lal and Tabu. Mohan Lal did the lead role (Georgekutty) in the original Malayalam movie (Drishyam), while Tabu would go on to play the role of the female Poilce officer (Meera Deshmukh) in the Hindi remake (also titled Drishyam)
One of the movies Suyambulingam (Kamal Haasan) is seen recalling when he obtains Varun's (Roshan Basheer) SIM card is the Hindi movie 'A Wednesday'. The story revolved around the Police trying to trace a suspected terrorist by using his SIM card identification. The movie was remade in Tamil as Unnaipol Oruvan (Someone Like You) in 2009 with Kamal Hassan and Mohan Lal as the leads. Mohan Lal did the lead role (Georgekutty) in the original Malayalam movie (Drishyam) which was remade as Papanasam.
In the final shot of the film,it is shown that someone closing his eyes Actually it is not kamal hassan but Mohanlal who acted in the original Malayalam version of the film.
In order to get the Tirunelveli accent, Kamal Haasan underwent training from writer Suga.