Memento (2000 )is a “dis-linear” thriller (Nolan’s term), presented in reverse chronology by a protagonist coping with a trauma-induced condition that prevents him from making new memories. Memento was based on a short story by Christopher Nolan's brother Jonathan, “Memento Mori,” published in the March 2001 issue of Esquire.
"You can’t trust memory. It’s an interpretation, not a record.”
Renfrew, Neff, and Daniel Argent. "'Remembering where it all began' Christopher Nolan on Memento." Creative Screenwriting, July 20, 2015.