Dr. Mierzwiak keeps following Joel through his memories and eliminating them. Mary Svevo adoringly looks on, gushing, telling the doctor that she likes watching him work. Stan steps out for some air. Mary starts reciting quotes to Dr. Mierzwiak, giggling like a schoolgirl. One of the quotes is from a poem by Alexander Pope, from which the film gets its title. As Mary recites the poem, Joel and Clementine gleefully watch a parade march through Times Square. Mary walks over to Dr. Mierzwiak and kisses him. She says she's loved him for a very long time. Dr. Mierzwiak shamefully tells her that he has a wife and kids. Mary is embarrassed, so Howard holds her close and comforts her.
Outside, Stan watches this intimate scene and Mrs. Mierzwiak drives up to the house. Stan honks the horn to alert Dr. Mierzwiak and Mary, but it's too late - Mrs. Mierzwiak sees them kissing. Dr. Mierzwiak races after his wife, saying it was a one-time mistake. Mary corroborates his story, begging Mrs. Mierzwiak to forgive her husband, calling herself a "stupid girl with a stupid crush" who forced herself on him. Mrs. Mierzwiak stops her car and tells Mary that she can have him, in fact, she has already been with Howard. Then, Mrs. Mierzwiak drives away, leaving Howard to explain to Mary that they did, in fact, have an affair, but then Mary asked for the procedure to erase him from her memory. Broken, Dr. Mierzwiak walks inside to finish the task at hand. Stan watches the scene unfold and offers the stunned Mary a lift.
Joel remembers coming to see Clementine at Barnes & Noble and asking her to go out with him. She comments that he's married, but he counters that he's not married - yet. Clementine is extremely straightforward about her expectations - if he's with her, he has to be with her. She is not going to be some adventure for him to find his "peace of mind" before getting married. Joel narrates that he remembers that speech, and claims that despite her disclaimer, he still believed that Clementine was going to save his life. He promises that it would be different if they could just do it all again, and she tells him to remember her. And then - she's gone again.
Mary Svevo is at the Lacuna, Inc offices, tearing through Dr. Mierzwiak's drawers until she finds her file. She listens to her own tape, and hears her own heartbroken voice confessing her feelings for Dr. Mierzwiak, and how she wanted to marry him and have his children. She breaks down, but his soothing voice tells her this is "for the best."
Joel remembers arriving in Montauk with Carrie and Rob, and helping them unload the car. In his voice-over, he says that this is the day that he and Clementine met. She sits beside him because he's sitting alone on the porch. She reaches over into his plate and takes a piece of chicken. He remembers thinking it was "intimate - like [they] were already lovers." He makes the classic jokes about her name, and says he loved his Huckleberry Hound doll as a kid. She tells him that this is it, and soon, she will be gone from his memory completely. They decide to enjoy these last moments together.
As the sun goes down, Joel and Clementine run in and out of the surf. She leads him into a dark house, and he tells her that he's got a live-in girlfriend. They break into the strangers' house and Joel is overly cautious, although Clementine is having fun. He keeps imploring her to leave, but she bounds around the house. She tells him that they are going to pretend the house is theirs for the night. Gleefully, Clementine finds the liquor cabinet and tells him to choose a wine. Then, the house (the memory of that night) starts to collapse. Joel tells Clementine that he has to go and catch his ride. She says, "So go." Looking back, Joel reflects that he left that day because he thought Clementine was a nut, but admits that he found her exciting. He wishes he had stayed, especially now.
The water laps over his feet and the frame gets darker. Joel tells Clementine that he left that night because he was scared, and that he could feel the disdain in her voice when she said, "So go." As he runs away, like he actually did, Clementine pokes her head back out and asks him to stay this time, to say goodbye - so they can pretend they had actual closure. He tells her, "I love you," and she whispers, "Meet me in Montauk." The frame becomes blurry, and Joel's final lingering memories of Clementine swiftly disappear forever.
As Joel tries to keep his memories of Clementine away from the Lacuna technicians, the memory sequences become more action-packed and thrilling. Visually, these scenes contain more contrast and dramatic lighting than has appeared earlier in the film, which creates the sensation of Joel and Clementine burrowing deeper and deeper into the recesses of his mind. Ellen Kuras says, "Michel's visual analogy... was inspired by the French film Le Boucher: a car is driving on a deserted country road at night, and you can only see what's illuminated by the throw of the headlights. When you're remembering something, you don't get a full picture; you only see certain glimpses of the scene in your head, depending on what you're focusing on" (Pavlus).
Lighting contrast is "the relationship in light intensity between the brightly lit areas and the shadow areas" (Ascher and Pincus 309). Often, higher contrast lighting makes the mood of the frame more somber and menacing. For most of Eternal Sunshine, Gondry requested Ellen Kuras to work with available light, and she made do with certain tools and tricks. She would attach a light onto the camera in order to illuminate only what was directly in front of it, or even have an actor hold a lightbulb to light his way. Gondry was influenced by the French New Wave directors, like Jean-Luc Godard, who eschewed smooth camera movements and slick lighting and instead preferred to use wheelchair dollies for movement and natural light for a more raw, realistic look (in Godard's time, most of these decisions were budget-driven).
Additionally, most of the visual effects in Eternal Sunshine were created in-camera, meaning that Gondry relied on illusions and stunts to create the surreal images. When Clementine is pulled away from Joel as they lie on the ice, Kate Winslet is actually hooked on wires that drag her across the floor. When Joel disappears and re-appears within the same frame in Dr. Mierzwiak's office, the crew created a hidden door for Jim Carrey to run behind and Gondry timed the camera movement to create the illusion. When pieces of memories become fuzzy, Gondry placed gauze over the lens of the camera.
Like Godard, Gondry's style of directing is also free-flowing and organic, and he prefers to shoot on location instead of on stages. He says that financial pressures almost forced them to shoot Eternal Sunshine of the Spotless Mind in Canada, but his desire for authenticity fueled the fight for them to stay in New York City. The Montauk scenes take place in Montauk, and the parade that marches through Times Square is real - they filmed it on the fly while shooting the scenes in Grand Central Station.
Gondry describes the final scene in Joel's memory, which takes place in the Montauk house the night Joel and Clementine first met (the first time), as one of the most difficult scenes for Jim Carrey to act. Carrey, known for his physical comedy, had a hard time standing stiffly while Kate Winslet was unleashing Clementine's looniness. Similarly, the version of Joel that occupies this memory vocalizes his desire to have been more of an active participant in this moment. However, Clementine is the person who pulls him out of his fear by convincing him that he does not need to stick to the path of the actual events of that day. He can fantasize a goodbye and even leave a message for himself - which ultimately works. This means that post-procedure Joel is much more in tune with what his heart wants, and this character development plays out in the final scenes.