Ra.One is a 2011 Indian science fiction film directed by Anubhav Sinha. The film stars Shah Rukh Khan, Kareena Kapoor Khan, and Arjun Rampal in lead roles. The movie revolves around a video game designer named Shekhar (Shah Rukh Khan), who creates a video game where the villain, Ra.One (Arjun Rampal), has artificial intelligence and is designed to be unbeatable.
Shekhar's son, Prateek (Armaan Verma), realizes that Ra.One is too strong for the game's protagonist, G.One (Shah Rukh Khan). He suggests to his father that he needs to make a more powerful hero to defeat Ra.One. Shekhar creates a new hero named H.A.R.T. (Hertz Activation Random Technology) who is more powerful than G.One.
However, during the testing phase, Prateek is forced to leave the game midway due to a power cut, which results in Ra.One gaining consciousness and coming to life. Ra.One then sets out to find its creator's son and kills anyone who comes in his way. Shekhar realizes the danger Ra.One poses and sends G.One to protect his son and stop Ra.One.
The rest of the movie follows G.One's journey as he battles Ra.One to save Prateek and ultimately defeat the villain. Along the way, G.One falls in love with Shekhar's wife Sonia (Kareena Kapoor Khan), adding a romantic subplot to the story.
Ra.One was one of the most expensive Indian films ever made at the time of its release and was praised for its high-quality special effects and action sequences. The film's music, composed by Vishal-Shekhar, was also a hit among audiences.