I Love You, I Love You (1968)

After a failed suicide attempt, Claude is recruited for a groundbreaking time travel experiment, never before tested on humans. However, a malfunction leaves him trapped in his past, forcing him to navigate a disjointed mosaic of memories in no apparent order. This cinematic marvel by Alain Resnais boldly navigates the realms of fantasy and memory, unraveling the intricate layers of the protagonist's psyche.