The Frozen II teaser is strikingly different from the original Frozen trailer, which goes to show: Disney really didn't know what they had with that film. A loose re-imagining of Hans Christian Andersen's The Snow Queen, Frozen told the story of Anna (Kristen Bell) and her older sister Elsa (Idina Menzel), a pair of princesses from the fantasy realm of Arendelle. The movie was an unexpected smash hit that grossed nearly $1.3 billion at the global box office and went on to win Oscars for Best Original Song and Animated Feature. As such, it came as little surprise when Disney finally announced Frozen II, with directors Jennifer Lee and Chris Buck returning and Lee once again pulling double-duty as the sequel's writer.

However, at the time of its development, the Mouse House clearly had no idea what Frozen would become. Back then, the studio had only just begun to make princess fairy tale movies again, having spent the 2000s dabbling in sci-fi (Treasure Planet, Atlantis: The Lost Empire, Meet the Robinsons) and working on films driven by talking animals (Home on the Range, Chicken Little, Bolt). They seemed wary of releasing a traditional princess adventure too, after 2009's The Princess and the Frog performed below expectations at the box office (despite being a modest commercial success overall). Disney's concerns were apparent in their subsequent marketing for Tangled, which the studio initially sold as being the opposite of an old-fashioned Disney fairy tale offering, along the lines of what DreamWorks Animation was churning out at the time. Their worries about Frozen weren't necessarily soothed by Tangled's financial success either, as evidenced by the film's original teaser.

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You wouldn't even know Frozen involves princesses at all, based on the first trailer (see below). The only characters that appear in the teaser are Olaf the snowman (Josh Gad) and Kristoff's reindeer Sven, as the pair spar over Olaf's carrot nose when it goes (literally) flying off his own face. Based on the trailer, one might think Frozen is an adventure about an enchanted snowman, as opposed to the reality of Olaf being a supporting character who doesn't even come to life until the film's second act. By comparison, the Frozen II teaser opens with Elsa trying to use her magical powers to cross an ocean, before teasing her and Anna's larger journey in the sequel.

It's easy to understand why Disney's changed their style when it comes to marketing Frozen II. For starters, Frozen is a bankable IP now, so there's no reason to hide that, at its core, the franchise is a story about the relationship between two princess sisters and their experiences together. The Frozen II teaser also hints at a darker and more dangerous adventure for Elsa, Anna, Olaf, and Kristoff (Jonathan Groff) to come - one that contrasts vividly with Olaf and Sven's light-hearted and silly antics in the original Frozen trailer. It makes sense, though, seeing as the kids who grew up watching the first movie are now six years older and ready for something a little more mature, both tonally and story-wise. The Toy Story films have done something similar, developing and changing in order to maintain pace with the generation of children growing up watching them. The strategy has worked wonders for that franchise, and it stands to reason that Frozen will continue to prosper by embracing a similar approach.

Of course, Frozen II is still a Disney movie and will have its fair share of kid-friendly elements, starting with Olaf and Sven's return. The teaser trailer also shows Kristoff and Sven charging through a forest alongside a large group of reindeer, some of whom may end up up having personalities as expressive and playful as Sven's. Further, Frozen songwriters Bobby Lopez and Kristen Anderson-Lopez are writing new songs for the sequel, which means Frozen II will be a musical affair, just like the first movie. Considering just how popular their Oscar-winning tune "Let It Go" was in the original film, it's possible that a future Frozen II trailer will offer a sneak peek of their music for the sequel.

If anything, though, that just goes to show how far we've come from the very first Frozen trailer - a preview that danced around revealing the film was about princesses (much less, a movie with musical numbers). Disney may've not known what they had with that film, but they're no doubt happy with what it turned out to be.

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