Over a decade after its emotional debut, Pete Docter is explaining the importance behind Carl and Ellie's heartbreaking Up opening sequence. The 2009 Pixar movie centered on an elderly widower traveling to South America with his house propelled by helium balloons with a hithchiking Wilderness Explorer in tow. Up debuted to near-universal acclaim from critics and audiences alike, garnering five Oscar nominations and winning two, though one seuence in particular has stood the test of time as viewers' favorite.

While speaking with The Hollywood Reporter to discuss his upcoming Winsor McCay Award, Pixar CCO Pete Docter reflected on the legacy of Up. In looking specifically at Carl and Ellie's heartbreaking opening montage, the director explained its importance to the film upon its release, and the challenges it raised for the studio's follow-ups. See what Docter explained below:

When we push past that, it’s always fun to surprise [audiences]. I would love to continue to push against those walls, in ways hopefully that are still tapping into things that the audience resonates with. It’s easy to do something different just for different’s sake. It’s really hard to do something different that still connects with people — so they want to see it, but they haven’t seen it before. That’s the hard part.

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Up's Opening Remains Pixar's Most Emotional Sequence To Date

Carl and Ellie looking up at the sky on UP

Up to the point of Up's release, Pixar had a reputation for their emotional storytelling, though it was around this time when the studio began branching off into more mature territory. The year prior saw WALL-E tackle themes of consumerism, waste management, obesity and humanity's negative impact on the world, all of which led to it becoming the second Pixar movie ever to be selected for preservation in the U.S. Film Registry by the Library of Congress, as well as the first from the studio to be licensed to The Criterion Collection.

Carl and Ellie's heartbreaking Up opening continued this Pixar trend. Beginning with their childhood meeting, the sequence progresses to their falling in love and marrying as adults, Ellie suffering a miscarriage, their plans to save up for a trip to Paradise Falls being impeded by life emergencies, and she eventually falls ill and dies. In addition to tackling the general theme of death, Up became celebrated for its sympathetic, and brutally raw, approach to exploring the dangers of attempting parenthood and other adult issues.

While some of Pixar's follow-ups have scored similar acclaim to Up, namely Toy Story 3 the year after, few have lived up to the same emotional heights of Carl and Ellie's heartbreaking opening. However, with the latter franchise set to come back with Toy Story 5 and the similarly emotional Inside Out 2 currently in production, it will be interesting to see if they can finally top the Oscar-winning sequence.

More: Disney’s New Up Short Makes Its Saddest Moment Even More ImportantSource: THR