Christopher Nolan’s Memento (2000), starring Guy Pearce, is a groundbreaking neo-noir thriller told in reverse chronology. Following Leonard, a man with short-term memory loss hunting his wife’s killer, the film combines unreliable narration, mystery, and psychological tension. A cult classic that established Nolan’s reputation, it remains one of cinema’s most innovative explorations of memory, truth, and revenge.

Leonard (Guy Pearce) suffers from a rare brain disorder — the inability to form any new memories. He can remember in detail everything that happened before his injury, but anyone he has met or anything he has done since that fateful night simply vanishes. Who are his friends? Who are his enemies? What is the truth? In Leonard's world, the answers to these questions shift and change from second to second. And the more he tries to figure out what is true and real, the deeper he sinks into a multi-layered abyss of uncertainty and surprises.

Från IMDB:
A former insurance investigator who now suffers from anterograde amnesia uses notes and tattoos to hunt down his wife's murderer.