The film began pre-production in early 2003 in a typical manner adapted by the director, Mani Ratnam, who keeps his projects under wraps until completion. The director chose to make two different versions of the film as he did not want the film to be dubbed, explaining that the essence of the script would be lost if they had done so. The project was named Aayitha Ezhuthu after the last letter of the Tamil alphabet, which is denoted by three dots in a triangle and the director revealed that the film was about three individuals. Early reports indicated that the film would be based on the 2000 neorealist Mexican film, Amores perros by Alejandro González Iñárritu, but eventually only the idea of hyperlink cinema was common in both films. However, Mani Ratnam revealed that the film was closer to Akira Kurosawa's 1950 Japanese film Rashomon as both films dealt with a cause-effect and a third-view called Rashomon effect.
The director initially opted against using songs in the film but wanted to create an album with A. R. Rahman for the project. However, after the songs were recorded, Mani Ratnam had a change of heart and chose to include them. For the art direction in the film, Sabu Cyril studied each character in-depth, giving them a distinct colour, mood, and background to suit their temperament. For Michael's house in the film, Cyril followed the arrangement in his own house and used some of his own photographs for decorations. He also expressed that he had great difficulty in re-creating the streets of Kolkata for the Hindi version of the film in Chennai. G. Ramesh was selected to be the hairdresser for the three lead actors in the film. 2b1af7f3a8