Original and intriguing film noir revision.

Rating: 9/10 (2 October 2001)

Revising such film noir conventions as a story told through the unreliable point of view and voice-over narration of a morally flawed investigator-protagonist, the pervasive infusion of a dark past into the narrative present, and the use of a femme fatale as an embodiment of evil allure, Memento is perhaps the most original and intriguing revision of the genre since Welles' Touch of Evil.
As almost every commentator has noted, the most startling (or 'gimmicky') feature of Memento - and one with obvious roots in the film noir tradition - is its inverted/contorted plot structure. The film loops backwards episodically to present a series of revelations about the main character, Lenny (Guy Pearce), about the motives of his antagonists 'Teddy' (Joe Pantolino) and 'Natalie' (Carrie Ann Moss), and about the nature of Lenny's memory-loss condition. His condition 'isn't amnesia' (or so Lenny tells everyone he meets) but rather such severe short term memory loss that he is unable to assimilate and retain experience - in other words, to make new memories. Consequently, Lenny's identity, or more precisely his self-knowledge, is arrested at the moment he received a blow to his head while trying to stop intruders from raping his wife.
Everything that has happened thereafter has no subjective reality for Lenny, only whatever 'objective' reality he can forge using instant photos, notes to himself, and - for the really important stuff - tattoos. But matters are even more complex and paradoxical than this setup might lead one to expect. Gradually, the viewer learns that even the clear memories that Lenny claims to have from before the assault are, like dreams, colored by protective distortions and selectivity. Moreover the so-called facts he has assembled in his investigation and that he defensively claims are more reliable than memory turn out to be irretrievably entangled in subjective motives: his own, Teddy's, and Natalie's. Thus the viewer's initial sympathy for Lenny as a justifiable victim/avenger transforms to horror as Lenny's true current identity becomes clear.
Importantly, Memento's regressive plot structure is punctuated and counter-pointed by a series of noirish black and white flashbacks in which Lenny relates to an anonymous phone caller the story of Sammy Jankis, another sufferer of short term memory loss who, ironically, was Lenny's big case in his pre-trauma life as an insurance investigator. Unlike the main narrative, the Sammy sequences are told in chronological order, strategically intersecting and organizing the narrative as it wends its way backwards to the moment when Lenny decides to set in motion the data trail that will lead to the murder we see him commit in the film's opening sequence. In addition, Lenny's reconstruction of the Sammy sequences is itself dreamlike and unreliable since he attributes to Sammy characteristics that (if we can believe Teddy, an utterly corrupt cop) are Lenny's own.
In addition to providing plot exposition and a recurring visual/narrative reference point, the Sammy sequences also bring into clear thematic focus the existential implications of memory loss. Like Sammy's, Lenny's 'condition' is a reduction to the most minimal and absurd level of the human mental processes for constructing meaning (in life, in film) out of fragmentary phenomena and evanescent recollections. In an age of Alzheimer's, deconstruction, and ego-fictions, most viewers will all-too-easily identify with Lenny's painfully hopeless and terrifyingly arbitrary quest to hold reality steady as is it fizzles and flits away.