Ghajini (2005)

Kalpana, a spunky and compassionate person, rents an apartment and works as an ad-model. Her life changes when she invents a love affair between herself and Sanjay Ramaswamy, a wealthy man. When Sanjay finds out, he decides to confront her to end this facade, but ends up falling in love with her.

He pretends to be poor, proposes to her, and she eventually accepts. Before they could get married, she is brutally murdered, and Sanjay is left to die after being mercilessly beaten up. Although his life is saved, he is left with short-term memory loss, a condition in which he cannot remember anything beyond 15 minutes.

During those 15 minutes, Sanjay manages to put together whatever he is able to recollect, through tattoos, Polaroid photos, notes, and maps on the wall of his apartment, and sets out to avenge Kalpana's death.

What he does not know is that the elusive killer knows about his agenda, and has already made plans to finish him off once and for all.