Riley's mental landscape is one of the most complex and fascinating parts of Inside Out. And the sequel to the Pixar movie, which has just been released in theaters, introduces a new element just as the protagonist enters the incredibly complicated stage of adolescence.

This is the Belief System, a very important trait in Riley's mind, and a part that greatly influences her development and personality. The fact that she thinks she is "a good person" or that she doesn't have enough courage can be crucial when making decisions, and it was essential to define this aspect correctly in the new movie.

In fact, this was something that the movie director Kelsey Mann and his producer Pete Docter acknowledged they were quite clear about. So they explain in the interview they gave to SERIES & MÁS | EL ESPAÑOL before the film's release in theaters.

'Del revés 2'

In Riley's mind

As we saw in the first movie, Riley's belief system is very well constructed, which is why the creators of Inside Out 2 wanted to delve deeper into this universe, expanding this range of abstract concepts.

"I think that's the best thing about this world and what made the first movie like that, the fact that they chose a concept like memories. It's something we can all identify with, but not all of us know how they look and how they actually work," observed director Kelsey Mann.

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"All of this is a lot of work, but we have a whole team of truly talented people who help us discover how it works and how it looks. And it's been very exciting to expand that world and that vocabulary now that Riley is a teenager."

Mann further elaborated on this idea, explaining what it was like to continue exploring the story in Inside Out 2. "We thought about what teenagers go through. You're starting to shape who you are as a person and to form your own beliefs. And we said 'beliefs, the belief system!'. We had to show the belief system."

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"We did this with a whole team led by our production designer, Jason Deamer. We made multiple versions of what it was like, and we ended up in a place that I'm very excited about. It's one of my favorite settings in the whole movie, because I think it's not only really beautiful, but it can also be very emotional. I think a lot of people can relate to it," he concluded.

"Actually, that's the challenge of the movie," added Pete Docter. "If you tell people the idea, they'll ask you to explain it. But if you show it to them, they'll get it. Our job was to make everything clear visually."