Ghajini (pronounced [ɡədʒniː]) is a 2005 Indian Tamil-language action thriller film directed by A. R. Murugadoss and produced by Salem Chandrasekharan. The film stars Suriya and Asin in the lead with Pradeep Rawat as the main antagonist, along with Nayanthara and Riyaz Khan in the supporting roles. Harris Jayaraj composed the soundtrack and background music, while R. D. Rajasekhar and Anthony were the film's cinematographer and editor, respectively. In the film, Sanjay Ramaswamy (Suriya), once an eminent businessman, develops anterograde amnesia due to a head injury he got while attempting to save his fiancee Kalpana (Asin) from getting murdered by a gangster (Pradeep Rawat). After that, he sets out to avenge her murder with the aid of photographs from a Polaroid Instant camera and permanent tattoos on his body.

This film is loosely based on Hollywood movie Memento.The film's production began shortly afterwards in April and was completed by September on the same year. The film was shot at Chennai, while two song sequences were filmed in Switzerland. It was dubbed and released in Telugu by Allu Aravind in November 2005, and received positive reviews with praise for the performances of the lead pair and the plot. It was remade into a Hindi film by Murugadoss again in 2008, with Asin, Rawat and Khan reprising their roles while Suriya's and Nayanthara's roles are played by Aamir Khan and Jiah Khan. The film's story takes inspiration from the Christopher Nolan film Memento (2000) and the 1951 film Happy Go Lovely.