Shrek 2
Shrek 2 is the perfect sequel to a subversive film of its time. Not only does Shrek 2 expand on the already beautiful world they've built, introduce characters that have been implied to exist but haven't been seen in the first movie like Princess Fiona's parents, introduce unique and fun characters like Puss in Boots and Doris, but also dive into the psychology of Shrek and the roots of Shrek and Fiona's relationship. The Shrek franchise fundamentally works because of the deep relationship between Shrek and Fiona, it is incredibly complex and subverts the tropes perpetuated by the Disney Renaissance era and the past fables and fairytales. Especially this movie builds on the first movie, showing a complex relationship between them that isn't built on sexual attraction (I think) but is built on genuine care and love between them. It is the classic enemies to lovers, but unlike most stories, their relationship transformation from enemies to lovers isn't purely physical, but built on trust, and true love for each other. There is absolutely zero filler scenes within the movie, which shows the incredible writing within the movie. It is able to tell a deep, concise, entertaining story that people of all ages can understand. And I think that is one of the best things a story can do, able to appeal to people of all ages while also having a profound message intricately interwoven throughout the story. An example of this would be Coraline, Kubo and The Two Strings, and majority of the older Pixar movies. And animation is especially a great medium to show these stories, which is why majority of beloved, well-known, and highest rated movies are animated.
Shrek 2's plot, like I said, has absolutely zero filler scenes, the story is so tightly woven through the dialogue, each of the characters, and how all of them are a foil for all of them. Shrek is a foil for the king and vice versa. The king is a foil for Fiona and vice versa. Donkey is a foil for Puss in Boots and vice versa. And the most obvious one, Shrek is a foil for Donkey and vice versa. The genius of Shrek 2 is all the interactions of each character, how they feel natural, and how it feels within character that Shrek would take in a cat with potential while Donkey would feel threatened by that cat potentially overthrowing Donkey's position as Shrek's number 2. It would make sense that Fiona would be hesitant to Prince Charming (pretending to be Shrek) because they're married at this point, and like she says in the movie, she fell in love with him and his personality. So, she is able to easily identify when "Shrek" is out of character. And with new characters with vaguely introduced backstories and personalities, you can create a lot of conflict from that. Like the king and queen of Far Far Away, aka mum and dad. We know they hid Fiona in the tall tower because of her ogre appearance, so we know that there is potentially some hostility from their part towards un-human creatures. And instead of making Fiona's parents this very discriminatory, hostile, mean royalty who rule over Far Far Away with an iron fist, they are shown to genuinely care for Fiona and do things within her best interest, even if it is what they assumed was in her best interest. Shrek and the king especially have a specific dynamic where they both care deeply for Fiona, and while they both seemingly have different ideas for what Fiona should do, they are both essentially doing the same to her; they both box her in, make her do things she doesn't want to, but they both believe are what's best for her. Shrek doesn't want her to go to Far Far Away to see her parents because of a bias he has towards them due to their treatment of her (being locked up in the tower, etc.) while the king doesn't want Fiona to marry Shrek because he is being blackmailed by the antagonist, Fairy Godmother (a legend) and also sort of has an unconscious bias towards ogres and other creatures. Both want Fiona to do something she doesn't want to, and are essentially two sides of the same coin.
Also the ending with Fairy Godmother singing "Holding out for a Hero" is one of the best endings I've ever seen. It is iconic, it is thrilling, and it is memorable and highly considered the peak of Shrek. I think the way they intercut the action with Shrek and the fairytale gang with Fiona and Charming dancing, as she is slowly convinced that Charming is Shrek is masterful. The audience knows that this is trouble, because of the scene previous, we don't know Harold did or didn't give Fiona the tea with the love potion. While you can take a guess and it'd probably be right, as a viewer, all you know is that there is one tea with a potion, you don't know which one he is going to give her, all you know is that the one she was reaching for was the one he didn't want to give her. That's it. You don't know if Fiona had changed his mind by giving her sad monologue about how she loved Shrek for himself. And as the intensity of Fairy Godmother's singing and the song increases, the action with Shrek and Fiona's dancing with Charming increases too, as your uncertainty rises to a peak. Unsure about what could happen and will Shrek get there on time? He didn't last time at the marriage with Fiona and Farquaad. The vocals Jennifer Saunders is serving in that song is amazing, she's a queen. And I also appreciate that while they did do the armour/sword deflecting the magic, that the magic still affects Harold (the king). He is still turned back into a frog, but the Fairy Godmother is also turned into bubbles. It is a sort of twist on the trope where usually the metal object deflects it and then the villain is gone. The twist with Harold being revealed to be a frog is also very intricately woven in throughout the story, clear from the beginning that that is what they wanted with Harold's character and not just a last minute plot twist for fun.
Shrek 2 is a masterpiece on how to create a perfect sequel. It must (1) expand on the existing characters while introducing new interesting ones that balance out the existing ones; (2) create a world that seems like it exists in the world created from the original and be able to world-build this new world (if they do create a new world) well; (3) be able to tell a story that not only has unique themes, but also be able to build off of the main theme of the original. I will never stop loving this movie, it is fantastic and I loved every aspect of it.