'Once Upon A Snowman' Directors Explain How 'Back To The Future Part II' Inspired Their 'Frozen' Prequel Short [Interview]

What happened to Olaf the talking snowman in the window of time between his creation and his first meeting with Anna during Frozen? The new Disney short Once Upon a Snowman answers that question. It turns out that Josh Gad's warm hug-loving character had a bit of an adventure, full of hijinks and existence-defining moments. And according to directors Trent Correy and Dan Abraham, it was all inspired by Back to the Future Part II.

Once Upon a Snowman is streaming now on Disney+, so before or after you watch it, you can read our interview with the filmmakers, who shared their inspiration for the short, how they made Olaf work as a central character, and whether there's a bit of Looney Tunes in their Disney character.

When did you realize there was a story to be told here about Olaf's first day? Was it born from you two, or was it brought to you?

Trent Correy: This story goes back to 2012. Frozen was my first film to work on at Disney, and I was actually a crowds animator animating background characters, because it was my very first show. The animators were working on "Let It Go" at the time, and one of our animators, Chad Sellers, has that great shot of Elsa making Olaf. And then she just walks away, builds her ice castle, and keeps singing. I was sitting there thinking, "There's a story here." I'm a fan of Pinocchio and Bambi. I want to see characters come to life and see the world for the first time. We don't see Olaf again until twenty minutes later in the film, when he meets Anna, Kristoff, and Sven. So I knew it was a story right away, and I kind of started writing down ideas and actually pitched it early on. But it wasn't until Disney+ came along that it really offered a platform for this short to be made. And Jennifer Lee, who had remembered that pitch from back in 2013, said, "Why don't we make this little Olaf short?" And that's when I got paired up with Mr. Dan Abraham.

So Dan, when you entered this, how was it pitched and presented to you?

Dan Abraham: Just that Trent here had come up with this short back in the day. When I heard the premise of it, I was like, "I want to see that short. I think that's a good sign that I want to know what that story is, and I'd love to be partnered up with him and figure this thing out." Because the idea of seeing Olaf's first steps and seeing him not only come to life and try to figure out who he is and where he is, and "Oh my gosh, I'm a snowman" – all of that just felt like so much fun that I wanted to be a part of it.

How do you split your duties as directors? Sometimes you see directing teams where one is the story person and one is the animation person. How did you divide the labor here?

Trent Correy: Well, it kind of happened naturally. I came from the animation department, and I just supervised Olaf on Frozen 2, and Dan comes from the story department and he had just finished the Olaf song in Frozen 2. So the marriage just worked out, and there were things that I got to learn about the story process that I wasn't privy to before, like watching Dan and our other three story artists board, and then Dan got to watch the production pipeline.

Dan Abraham: That was so cool. For Trent to give notes on story and for me to give notes on animation, it was like, "You've got your chocolate in my peanut butter." It worked so well. A lot of times, one of us would say, "I'm not sure what the terminology here is, but there's something –" and we [understood each other]. It was a really great learning process for both of us, and we both fully embraced it and had a ball.

There's a long tradition of seeing a famous tale from an alternate angle. Did you take any inspiration from those kinds of stories? Was there a mental checklist of plays, movies, or TV episodes that inspired this?

Dan Abraham: For me, it's Back to the Future Part II, when he goes back to 1955 again. I love that part of the movie and think it's so much fun, and it's got a flavor of that in Once Upon a Snowman, for sure. We're seeing things from a new perspective, and there are near-misses. There's a lot of influence and moments from the first movie that are in our short.

Trent Correy: I love Back to the Future as well, but also, Pixar has done – I love Dug's Special Mission. That's a short I watched that's a great little behind the scenes from Up. I remember as we were developing Once Upon a Snowman, Avengers: Infinity War came out, and there's that great behind the scenes of Chris Pratt dancing from Guardians of the Galaxy with his music on from a different angle. We had already developed this short, and I sat there thinking, "This could work."

In the Frozen films, Olaf is used in small doses in ways that are really effective. But here, he's front and center. What were the pitfalls – and also, maybe the positives – of making Olaf a lead? What were things you had to watch out for to make sure he was suitable to take center stage?

Trent Correy: I think you're right. I think the easy thing would be to make him talk all the time. Sometimes his quiet moments or his pantomime moments are just as special. So I'll hand it to Dan and Josh Gad who kind of know the character that way too. But I think involving Oaken as a character to play off. In the original pitch, Oaken wasn't as big of a character, and involving him in there gives you a bit of a break and time to enjoy the moment in the story.

Dan Abraham: I think if the story was all madcap silliness and Olaf being wacky, I think that it wouldn't be as intriguing, it wouldn't be as fun to watch. But we've got this side where Olaf is trying to figure out his identity, and he's on a mission. He's extremely optimistic about it, and he's positive like Olaf is, but the way that Josh Gad brings in that heart, like you were saying, and the humor and pathos, all that stuff, it makes for a character that's well-rounded enough. Even though, for the most part, he's the funny character, but he's very well-rounded, and he's not only watchable, but likable.

This short runs a tight seven minutes, and I love that. I love when any movie of any length knows when to get in, tell its story, and get out. But what did you have to kill? What did you love that's not in this short, that had to be sacrificed to make sure you could have this pacing?

Trent Correy: I think the length of it, because it's Disney+ and streaming, we're kind of just able to create a length that's right for the story. I'm like you: I have – not a short attention span, but I like watching shorts that don't overstay their welcome. I think we have this great board artist named Seth Boyden, who probably storyboarded what could be a five minute chase sequence of hilarious gags that we've never seen before with Olaf. The hardest part was probably trying to choose which ones we liked best.

Dan Abraham: That's what I was going to say, too. He gave us so much gold, and to have to only choose the ones where you leave the audience wanting more, it was such an amazing job of having the action build and build and build. But other than that, there really wasn't a lot that we left on the cutting room floor. The story guided us as to how long it wanted to be. I wouldn't change anything, honestly.

My favorite gag in the short is when Olaf's head attaches to his legs and starts running on its own. I'm curious where you draw your inspiration. I know you're Disney guys, but I feel like there's a little bit of Looney Tunes in Olaf. Where do you draw from for those kind of sight gags?

Trent Correy: I can start by saying that I grew up on the Looney Tunes shorts and Disney, so I love both. The nature of the character of Olaf, you give him to a story artist and say, "Do a crazy chase sequence," and then you give him to an animator and say, "Go to town and break him apart." What started off as sketches of, "Oh, it'd be funny if he had these flamingo legs" just ended up being a joy to watch animate. So, all those things you mentioned.

Dan Abraham: Man, I grew up on Saturday morning cartoons and going to the movie theater to see Disney features. That's what lit me up my whole life, so I take such inspiration from the Looney Tunes and the Hanna Barbera and all that, but then in Lady in the Tramp when Trusty gets hit by that dogcatcher wagon...all that stuff. I'm getting chills right now. I just live for that. It's just genius bits of silliness and poignancy. I love it.

This is a short made for people who know Frozen inside and out. Is that freeing to know that you can make the movie and know that people who are going to watch it are Frozen fans, or is it difficult to have that hurdle? Is that the greatest barrier, or the greatest open door?

Trent Correy: Well, I will say the greatest door opening is starting with "Let It Go." Who doesn't know that song? That was always part of the original pitch: start with Elsa singing "Let It Go," and get right into the story. I'll let Dan jump on this because he kind of led the way on the story side of this part, but because it's about Olaf trying to discover who he is and his identity, I think it's a very relatable and common story. Really, that other stuff was just kind of icing. I hope that anyone who hasn't seen the original movie will still be able to follow Olaf's search for his identity.

Dan Abraham: Yeah, I think it's a standalone thing, but it was a lot of fun to know that the vast majority of the people that watch this are – my God, people have watched and re-watched Frozen so many times that they're going to be looking for all those little moments. So to know that we were giving them that fun and that wink to the original, it's a lot of fun.

Trent Correy: Plus, Dan and I are fans. So we're like, in the story room, "Oh, what if Olaf started the wolf chase? What if the wagon that crashes and blows up crushes his carrot?" It's kind of fun to develop those ideas.

That's a huge benefit. The people who are paying for Disney+ every month have seen Frozen. They're going to know what you guys are shooting for here.

Trent Correy: (laughs)

Dan Abraham: Yeah, exactly.