The opening sequence to the 2009 Disney-Pixar film Up (sometimes referred to as "Married Life" after the accompanying instrumental piece, the Up montage, or including the rest of the prologue The First 10 Minutes of Up) has become known as a cultural milestone and a key element to the film's success.

While the core concept of the film was to have a house float into the sky with balloons, the filmmakers needed a rationale for why a character would do such a thing. Their solution was to show the entirety of a married couple's relationship from the first day they met to the day the wife died. They envisioned it as a wordless montage that would play like a series of Polaroid home movies. Director Pete Docter always felt that an expository sequence to open the film was important because if the viewers do not love the characters, "then [they're] not along for the ride." In an early draft of the Ellie–Carl meeting, Carl is trying to capture a bird with a trap and Ellie punches him in the face, yelling about animal rights. This led into a montage sequence of a "lifelong sneak-attack punching game, lending the script some heart in a 'non-sappy' way", according to the Huffington Post. Co-director Bob Peterson said "we thought that was the funniest thing", noting that even when Carl visited Ellie's sickbed, she gives him a feeble slap. Nevertheless, the test audiences did not warm to the sequence. Docter explained "We showed it, and there was silence. I guess they thought it was too violent or something". From that point on, the filmmakers went with a sorrowful version of the sequence.

In one cutting room session, one part of the sequence in which Ellie is despondent having learned she is not able to have children, received many notes from members of the studio, believing the moment may have pushed things too far. As a result, the scene was cut, though later put back into the film. Docter explained: "You didn’t feel as deeply [without the scene] — not only just [within] that sequence, but through the whole film. Most of the emotional stuff is not just to push on people and make them cry, but it’s for some greater reason to really make you care about the story."

The "Married Life" piece was the first assignment that composer Michael Giacchino had on the film. He explained: "We knew that was going to be one of the most difficult scenes in the film, so we tackled that first, and I was just working really hard to make that scene really work because I knew that was going to inform the rest of the story". Originally he had written a different piece to be played in that part of the film, but Docter requested a song that would play as if from one's grandmother's music box. Giacchino subsequently conceived of the new composition. After recording the initial piece, they went back to make touch-ups at various points to match the emotional tone of the visual sequence.

The scene "sketches out Carl's early married life with childhood sweetheart Ellie". In general definitions, the 'sequence' excludes the earlier parts of the film's prologue in which Carl watches a filmreel about Charles F Muntz and has a dialogue sequence with Ellie. The sequence is "only minutes in length and almost completely silent".

The sequence begins with a flash of a camera at their wedding, followed by their first kiss, which is applauded by Ellie's lively family as well as Carl's stoic family. After fixing up the house where they met to match Ellie's childhood drawing, they spend their marriage doing three main activities: watching clouds, working at the zoo (Ellie as a tour guide and Carl as a balloon salesman), and reading together. During one cloud-watching session, Carl points out a cloud that looks like a baby. Inspired, they decide to conceive a child and prepare a nursery, but as the music slows, the two learn at the doctor's office that their attempts to have a child have failed (with it being implied that Ellie either had a miscarriage, or is infertile) leaving them devastated. At their house, Carl brings Ellie her childhood scrapbook, which consoles her. They begin to keep a spare change jar to save up for Ellie's dream trip to Paradise Falls. However, several events, including a flat tire, Carl breaking his leg, and the house getting damaged during a storm, cause them to repeatedly break open the jar early.

A montage of Ellie tying Carl's ties through the years follows, showing them getting ready for each day of work at the zoo, the last one being a bow tie, which Carl will keep in for the rest of his life (it's implied that he doesn't know how to tie a tie). It is followed by them slow dancing at home, now in their old age, the spare change jar having been shelved and forgotten. As they fix up their house, where they will spend their retirement, Carl looks upon Ellie's art, representing her dream trip, and realizes he has yet to fulfill his promise, which almost stops the music entirely. He gets an idea and goes to a travel agency to buy tickets for Paradise Falls and takes Ellie cloud watching, bringing the tickets with him on a picnic to surprise her. However, Ellie struggles to reach Carl and collapses as her husband runs to her side.

As instruments drop out of the harmony, leaving only a piano, Carl brings a dying Ellie a balloon to the hospital just like she did with him the night he made the promise as a child. Ellie pushes her scrapbook to him, and he kisses her on the head. In the church where they married, Carl is still holding the balloon, seated on the steps up to where Ellie's casket was during her funeral. As he climbs up the steps, they become the steps to his home. He sadly disappears through the door and pulls the balloon in after him. The screen fades to black as the music ends.