When a film makes you cry, it isn't an accident. Someone engineered it.
Start with what the feeling actually is. The researchers Alan Fiske, Beate Seibt and Thomas Schubert call it kama muta, Sanskrit for "moved by love."
In a study published in 2019, they and dozens of colleagues measured it in 19 countries and 15 languages, with 3,542 participants. With some variation between cultures, the same pattern held in every sample.
For me, this movie was about a rat who cooks.
Ratatouille.
It starts from a contradiction that Brad Bird, who took over as director, said is what drew him in: "What's the one thing that all kitchens fear the most? Rats. So imagine if you had a rat whose only ambition was to become a master chef."
That contradiction is where the caring starts. Remy wants the one thing his own body rules out. Nobody has to tell you to root for him. Every time he walks into a kitchen, you already know what happens if someone sees him.
Bird made that gap visible. When he took over, the rats had been turned into little humans that walked on two legs. He put them back on all fours, he told The Hollywood Reporter in 2007, "so we could see our main character choosing to emulate humans." Remy walks upright to keep his front paws clean for food. In front of his father he has to go on all fours, and when he feels shame he goes back to moving like a rat. Bird called it "a way to physicalize his emotional state." You can tell how Remy feels from how he stands.
The important part is that now the audience can also relate to Remy.
The impossible task everyone says we can't do. The feeling of proving people wrong.
Then the film gives the impossible a few rules and sticks to them. Linguini can't understand a word Remy squeaks, so Remy hides under his chef's hat and steers him by pulling his hair. They practice at night, Linguini blindfolded, until it works. It's absurd, but once you've watched them learn it, you stop asking whether a rat could cook. You start worrying about whether he'll get caught.
Now you don't just relate to the characters of the story. You're invested in them. There's now a solution, but will they succeed?
So now the next logical step is to reinforce bonds, but also pull them apart. When Remy says he isn't staying with the colony, Django takes him to a rat-trap shop with rows of dead rats in the window.
"You can't change nature," Django says. "Change is nature," Remy answers. Later Remy and Linguini fall out, and Linguini throws him out of the kitchen with the rest of the rats.
And then, at the worst moment, the story keeps punching down.
Skinner catches Remy in a trap, and Django and Emile come to free him. Linguini tells the kitchen the rat is the real chef, and the whole staff walks out. Then Django walks in with the colony and tells his son he's willing to help. The father who showed him the dead rats is now in a human kitchen, working for his son.
There's one more rule, and it's the easiest one to forget. Don't hand over the feeling. Andrew Stanton (director at Pixar) calls it two plus two: "Don't give them four, give them two plus two." The audience, he says, "actually wants to work for their meal." The tear comes when the viewer puts the pieces together themselves. Tell them to cry and they won't.
None of this is only about films. Anything people have to feel, a pitch, a launch, a letter, a post, runs on the same spec. Bring them inside. Make them care about a bond. Push it apart. Close it suddenly, and let them do the last step.