Believe it or not, Christopher Nolan's vertiginous sophomore effort, Memento, turns 20 years old this calendar year. The thrilling nonlinear crime story put Nolan on the map as one of the most talented, unique, and original new voices to hit Hollywood. Two decades later, Nolan has become the preeminent purveyor of high-concept artistic blockbusters. His work in The Dark Knight trilogy, Inception, Interstellar, and Dunkirk speaks for itself.

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As we await word on whether or not Nolan's newest film, Tenet, will be released this July as planned, now is a perfect time to redirect our attention towards Memento. Check out these 10 hidden details everyone missed in the movie!

Jimmy G.'s Origin

The underlying conflict of Memento concerns Leonard (Guy Pearce) determined to find his wife's unidentified killer. Without a name to go on, Leonard gives the killer the alias Jimmy G. But do you know where this name came from?

In the book The Man Who Mistook His Wife For a Hat, Dr. Oliver Sacks treats a patient named Jimmy G. The patient, much like Leonard, has a rare form of retrograde and anterograde amnesia, meaning he can't form new memories. While Jonathan Nolan inspired the script via his short story Momento Mori, Sacks' work was more than inspirational.

Chronology

Believe it or not, the edit of Memento jumps in narrative chronology a whopping 113 times. Furthermore, a closer inspection of how the film is constructed reveals a precise formula.

The movie is cleaved into two narrative strands. The present is represented in the color scenes and given a reverse alphabetical sequence (V-A). The flashbacks are filmed in black and white and given a linear numerical sequence (1-22). When combined, the narrative sequence of the film plays as follows: 1, V, 2, U, 3, T, 4, S, 5, R...etc.

Handwriting

Glean whatever clue you might from this here factoid. During the entirety of the film, Leonard uses thick block lettering when scrawling the various notes and tattoos to help bolster his memory. Well, all but one. Have you spotted the lone outlier?

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When Teddy implores Leonard to write down "do not trust her" in regard to Natalie (Carrie-Anne Moss), for whatever reason, Leonard writes the note in handwritten cursive rather than his trademark block lettering. He later scratches out the note, implying that something was amiss all along.

Self-References

Nolan has a pretty fun time calling attention to himself and that of his wife, Emma Thomas, in a few background details in Memento. Care to guess what they are?

The first happens to be the tattoo shop Leonard frequently visits in the film. In honor of his wife, Nolan named the shop Emma's Tattoos. Not to be outdone, however, Nolan later adds another personal touch by placing his own white Honda Civic in the parking lot right next to Leonard's Jaguar. Sneaky!

ADR

Teddy and Leonard talking in Memento.

In film parlance, ADR stands for Automated Dialogue Replacement. It's a process of re-recording dialogue that, for whatever reason, didn't come out as originally planned during the shoot. In Memento, Nolan hides a piece of his own ADR in plain sight!

When Teddy utters the key line "You don't have a clue, you freak," actor Joe Pantoliano didn't quite nail the last two words to Nolan's liking. As a result, Nolan recorded his own reading of the line, which is what you hear when Teddy completes the "you freak" portion of the statement.

Sammy/Leonard Splice

Sammy looks concerned in Memento

Not to spoil the plot, but the character of Sammy Jankis (Stephen Tobolowski) is thought to be a mere self-reflective figment of Leonard's warped imagination. A hidden visual clue in the film directly reinforces this theory.

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Following the death of Sammy's wife, he is shown sitting in a mental hospital. Just as someone ambles in front of Sammy, and right before the film cuts to a shot of Leonard on the phone, a quick insert of Leonard sitting in Sammy's hospital chair is subliminally flashed onscreen.

Leonard's Chest Tattoo

One of the most iconic still images of the film showcases an ebullient Leonard pointing to a blank spot on his chest. He tells Natalie he's leaving the spot open until he locates Jimmy G. However, a flashback shot indicates Jimmy G.'s identity right before our very eyes.

When Leonard drives to the tattoo parlor, he flashes back to a memory of him and his wife in bed. If you pay close attention, you can see that the blank spot on Leonard's chest that was once bare is now filled with a tattoo that reads "I've Done It."

Teddy's Phone Number

Does Teddy's phone number 555-0134 ring any bells? Well, it happens to be the same phone number Marla Singer had in Fight Club, released one year prior. While that's freaky enough, there's more to Teddy's phone number.

Much of the narrative involves Leonard speaking on the phone with people he cannot remember. During one scene, he holds a picture with the 555-0134 number written on the bottom of the image. This is a sly clue that Leonard has been talking to Teddy the whole time, who we later learn is a police officer helping Leonard avenge his wife's murder.

V-Neck Photo

Natalie offering a piece of paper to someone in Memento.

Another chilling visual parallel between Leonard and Sammy is drawn in the background of Memento. When Leonard watches TV at Natalie's, a picture behind him shows a needle and person wearing a white V-neck shirt. Any idea what that means?

Sammy Jankis accidentally murdered his wife by overdosing her with insulin while watching TV. Even eerier, the same white V-neck seen in the photo is the same garment Leonard's wife wears in another flashback scene.

DVD Easter Egg

Perhaps the coolest hidden detail found in Memento comes via the DVD supplemental material. By accessing a hidden Easter Egg on the Limited Edition DVD menu, you can unlock a version of the film that plays in linear chronological order.

Even more rewarding, one must correctly answer a series of questions and solve a puzzle in order to unlock the complete linear version. The task is made even harder by virtue of the disabled rewind, fast-forward, and chapter skipping buttons.

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