Now streaming on Disney+, Into the Unknown examines the scope of production for Chris Buck and Jennifer Lee's 2019 film, Frozen 2. The six-part docuseries offers a variety of behind-the-scenes reveals, whether it's anecdotes from cast members, under-the-pressure stories from animators, or day-to-day commentaries from the producers and directors - and the documentary reveals quite a bit about how much the film changed over the years.

When Frozen 2 released in November 2019, critics and general audiences raved about the cinematic experience as a whole but noticed darker themes. The original 2013 film became a pop culture sensation, most notably because of the central storyline involving sisters Elsa (Idina Menzel) and Anna (Kristen Bell), and the complementary musical anthems like "For the First Time in Forever" and the Oscar-winning hit "Let It Go." Plus, the snowman Olaf (Josh Gad) offered comedic relief for audiences of all ages. Despite Frozen 2's darker storyline, the sequel became a massive box hit and has been praised for its accessible and cryptic themes. Into the Unknown on Disney+ shows why certain Frozen 2 moments were cut, and why others were tweaked for specific demographics.

Related: Frozen Theory: Elsa's Powers Can Control More Than Ice

Into the Unknown covers every aspect of the Frozen 2 production process and thoroughly chronicles the hard work that affects every frame of the film. For storytelling purposes, the docuseries consistently returns to issues that hold up production, or at least make it more complicated. Here are several reveals from Into the Unknown that will interest Frozen 2 fans.

Frozen 2 Animators Used Themselves For Reference

Into the Unknown: Making Frozen 2 on Disney+

Frozen 2 animator Malerie Walters appears in three episodes of Into the Unknown, and explains how a team of 70 animators worked together to bring character movements to life. She discusses the process of seeing the "bigger picture," and how the film could benefit by providing feedback to the directors. At one point, writer and co-director Jennifer Lee talks about animators typically being "shy" people who "shine" by taking ownership and creating "living, breathing" characters. In a "dailies" meeting, Walters and Lee discuss Elsa's movements during the "Into the Unknown" sequence, and how they could become more believable.

Walters describes the overall Frozen II experience as "nerve-wracking," simply because she hadn't animated Elsa before. After receiving creative notes about the animation being "too clumsy," Walters had her boyfriend ride a skateboard and record her while running down a sidewalk. Frozen 2's Elsa was then animated based on the video reference, with the motivating factor being that kids would one day mimic each and every movement on-screen. Walters then explains how she viewed Elsa as an ice skater while approaching a ledge, and how the "shh thing" would make the most sense for the character's movements.

Everybody Was Confused About "The Voice" In Frozen 2

A board meeting in the documentary Into the Unknown: Making Frozen 2 on Disney+

In Frozen 2, a voice calls Elsa to the Enchanted Forest, and essentially serves as the inciting incident that sets the events in motion. It's later shown that the voice is actually the spirit of Elsa and Anna's mother Iduna (Evan Rachel Wood), who was raised in a land called Northuldra before meeting Agnarr (Alfred Molina). Surprisingly, Into the Unknown reveals that the true identity of the "Voice" was confusing to many Frozen 2 collaborators, and that everybody had different opinions.

More: Frozen 2's Post-Credits Scene May Introduce An Elsa Plot Hole

In the third episode of Into the Unknown, Lee reveals that she achieved clarity about the "Show Yourself" sequence by "finally making a decisions about the Voice." Songwriters Kristen Anderson-Lopez and Robert Lopez added a lullaby reprise, which led to everyone involved deciding that the Voice would "definitely" be Elsa and Anna's mother, Iduna. By making that decision, the filmmakers could then more effectively process feedback from test screenings, resulting in a more accessible and clear storyline.

Frozen 2's "Show Yourself" Was Almost Cut

Frozen 2 Elsa Show Yourself

Before Iduna was incorporated into "Show Yourself," the song itself was "in flux." Writers Kristen Anderson-Lopez and Robert Lopez spent 24 hours re-working the front end, hoping to find a "new energy." According to the musicians, the main problem was that the original version was too aggressive, and that Elsa needed to have a more reflective moment of awakening. The songwriters perform their original song opening in the docuseries, which involves rapid piano notes and a declarative vocals. Because Elsa seemed to be "coming in hot" and that her attitude wasn't "justified," they took a more organic approach and began with a gentler and more conversational approach. The songwriters ultimately had disagreements with Lee about the tone and mood of the song, which inspired more compositional tweaks. It came close to being removed altogether, but they finally figured it out in the 11th hour of production.

Frozen 2's Test Screenings Led To Story Clarity & More Comedy

Josh Gad as Olaf from Frozen 2

Hoping to learn more about how audiences would engage (or not) with Frozen 2, the filmmakers held a surprise screening in San Diego. Viewers were asked to provide feedback about plot points that were confusing or that weren't seemingly resolved by the end of the movie. The directors eventually realized that some people didn't understand the original movie intro, as it involved an unfamiliar location and unfamiliar male narration. The issue was resolved by flipping the opening structure, and by showing young Elsa and Anna with their parents. More comedy was also added for kids, most notably a sequence in which Olaf recaps the original Frozen movie. It's a moment that at once entertains while providing the necessary clarity for all demographics. Some of the Olaf jokes were also tweaked to reflect the perspective of young children. Plus, they realized that Bruni was a big hit with audiences, and so they sought to add him into the film a bit more.

The Frozen 2 Doc Reveals The Full Scope Of Production

Into the Unknown: Making Frozen 2 on Disney+

As a whole, Into the Unknown reveals how various departments work independently, but also how they're all connected in terms of creative clarity. At one point, Frozen 2 animators learn that their work has been cut from the film, but seem to recognize that the end product will improve as a result. The final episodes of the Disney+ docuseries heavily focus on test screening feedback, which leads to stressful deadlines for the various creatives who don't necessarily understand how the focal story will change from day to day - and there was no way they were going to miss the film's release date. The animation sequences spotlight the small details that are so important, along with various moments involving sound design and lighting for both characters and settings. The Disney+ docuseries builds to a chaotic fifth episode, as "the department head of department heads (visual effects supervisor Steve Goldberg)" looms over the entire Frozen 2 production to ensure consistency and clarity for audiences, along with a dazzling cinematic experience.

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