Genius scientist Vashi (played by Rajnikanth) is deeply invested in designing an intelligent robot, pouring a lot of energy and emotion into it, modeling it after his own appearance, teaching it various skills, and having it by his side to help it adapt to society as quickly as possible, naming it 'Chitti' (also played by Rajnikanth). Due to his dedication to work, he neglects his girlfriend Sana (played by Aishwarya Rai), and to cheer her up, he agrees to let Chitti accompany him during his final exam preparations. At first, Chitti causes a lot of humorous incidents, but as time goes by, the multifunctional robot begins to demonstrate its exceptional abilities in every aspect of life, and through interactions with Sana, it develops human emotions and gradually falls in love with her. The jealousy of love creates a rift between Vashi and Chitti, and Vashi's teacher seizes the opportunity to encourage Chitti, inserting a virus chip that turns Chitti into a killing machine. A continuous production of Chitti robots ensues, plunging the world into chaos. Scientist Vashi allies with the military to fight to save the original good-hearted Chitti. The film cost around 1.65 billion rupees (about 35 million USD), making it the most expensive film in Bollywood history. It also set multiple 'firsts' in the history of Indian cinema.