Sanjay Singhania is a fictional character from the Bollywood film Ghajini, portrayed by actor Aamir Khan. He is a successful businessman who suffers from short-term memory loss due to a traumatic incident. This condition leads him to use photographs and tattoos to keep track of important information, particularly about his quest for revenge. The film explores themes of love, loss, and the impact of memory on identity. Sanjay's character is driven by his desire to avenge the death of his girlfriend, Kalpana, played by Asin. His journey highlights the challenges faced by individuals with memory impairments and the lengths one might go to for love.