It's a kids' movie. But it might be the smartest, saddest film you'll see this year.

Seriously, bring tissues.

This morning, before work, I went to the movies and I cried. The little girl next to me cried too. So did her mum. Her mum was actually bawling by the time the lights came up.

Tears. That’s pretty much the response that Pixar’s new film Inside Out has elicited in every adult I’ve spoken to about it.

So. Many. Tears.

The thing is, nothing all that sad really happens in this film. There is loss, sure, but it is the ordinariness of it all that really gets you.

The narrative of the film is pretty simple. Riley, an 11-year-old girl, is upset when her family relocates from Minnesota to San Francisco.

Her new home isn’t quite what she’d imagined; her local pizza place only stocks weird organic pizzas, her dad is busy and stressed about work and her best friend is on the other side of the country.

No, it’s not the stuff of great tragic drama, but as anyone who has been a kid knows, these kinds of big life changes can wreak havoc in a child’s inner world.

And that’s where all the action of this film takes place, inside little Riley’s head.

Here we meet her five emotions personified in Joy, Anger, Disgust, Fear and, of course, Sadness.

Every day they fight it out over the controls in Riley’s brain and help her sort through the day’s events. Everyone has a role to play, but it’s pretty clear that Joy is running the show.

Sure enough though, as things in Riley’s life become more complex and hard to cope with, so does managing her emotions and Joy finds it increasingly difficult to keep Sadness under wraps.

In her desperation to repress her beautifully glum friend, the pair are accidentally banished to Riley’s outer brain and have to work together to find their way back.

There is so much about this movie that I loved. Parks and Recreation fans will be happy to know that Amy Poehler as Joy is as likeable and unflappably optimistic as Leslie Knope ever was; and Mindy Kaling is at her sassiest as the voice of Disgust.

The whole thing is completely hilarious whether you’re five or 45. Like all of Pixar’s efforts the animation is spectacular and the entertainment is non-stop.

Just like the company’s other films there are also poignant lessons to be learned and a whole lot of feels (I think we all remember the opening sequence of Up, which to be honest I am still not quite over).

Yet, even amongst it’s predecessors, Inside Out is still a stand out, not least because its lead is an 11-year-old girl.

Hollywood consistently tells us that films with female protagonists simply don’t make money — audiences just don’t want to watch women, apparently.

Not only is this blatantly untrue — Inside Out had the highest-grossing opening weekend of any original film (take that, Hollywood jerks) — it also tells young girls that their experiences aren’t valuable, at least, not as valuable as those of the boy sitting next to them in class.

When it come to films aimed directly at children, the problem only becomes more pronounced as female characters are consistently sidelined, and if they’re not, well, they’re probably an effing princess.

One of the most appealing things about this film is that Riley is a girl. Not a princess. Just a girl.

She is a normal girl with normal worries and no imagined nation-state to reign over.

She worries about school, her parents, her friends, playing hockey – this shouldn’t be ground-breaking, but it really really is.

Name me one mainstream, animated kid’s movie with a young girl at the centre whose brain matters more than her beauty?

Oh, you can’t?

THAT’S BECAUSE NO SUCH FILM EXISTS.

Yes, Riley’s parents played into out-dated gender stereotypes — her mum, while lovely, seems to be unemployed and when we’re first allowed to peek inside her father’s brain there’s nothing in there but sports (sigh) – BUT this doesn’t take away from the fact that their on-screen daughter is clever, complex and her mind is the centrepiece of this film.

I love Riley and tiny me would have loved her too.

Watch the trailer here (post continues after video):

The second thing that makes this film so special is the way that it deals with loss.

As children we are consistently told that we should be happy — or at least trying to be happy — all of the time.

And it’s just not realistic.

Inside Out is the first film I have seen for kids that challenges this idea and tells them not just that it’s okay to be sad, but that they should be sad, at least some of the time.

As Joy grudgingly drags Sadness through the various levels of Riley’s psyche she begins to realise that Sadness’ unique and gloomy world view is just as crucial for Riley’s well being as her own relentlessly positive one is.

In a lot of ways Sadness is really the hero of the film and many of the most thought-provoking and moving moments come from her.

I knew I was going to cry in this film even before I saw it. But I didn’t know why.

I did cry, obviously, but it wasn’t from grief. Rather it was from recognition. Riley’s struggles are totally, mundanely human and absolutely familiar.

Loss and change are part of everyone’s lives and sometimes it’s important to stop and acknowledge them. Feel sad, have a bit of a cry. Then you can get on with your day.

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