The problem that often occurs in these sequels is that they've exhausted the possibilities inherent in their original stories. But two of my favorite sequels of 2015--Magic Mike XXL and Pitch Perfect 2--manage to sidestep this issue by regarding their originators as a stepping stone and not as a template.
In a way, the two have sloughed off the trappings of their "origin" stories, freeing them to fulfill and explore ideas more fundamental to their identities. As much as Magic Mike is about its titular character, nearly as much time is devoted to the exploits of The Kid and his sister, with whom Mike is having a budding romance. There's also the subplot of the failing economy, with Mike's increasingly dire dreams of starting his own business. In Magic Mike XXL, these asides are quickly and purposefully tossed away. Big Dick Richie even literally tosses Mike's cell phone out of the window as he constantly tries to keep track of the business back at home. The Pitch Perfect movies may more obviously possess the trappings of the musical, but by eliminating most of its predecessor's narrative threads, XXL also approaches the traditional genre's structure.
The story, such as it is, has Mike rejoining The Kings of Tampa as they drive from Florida to Myrtle Beach to put on one last show at a major stripper convention. (By the way, is there really such a thing and how does one get tickets?) And just like the plot in a musical is often merely the stuff in between the songs, the road trip here is little more than a clothesline on which to hang all these set pieces. The focus is almost exclusively on performance and the joy of those performances, both for the audience and the ones on stage.
Even the one set piece that isn't specifically a dance number is able to marry the dual themes of performance and pleasure. The scene involves the guys accidentally crashing a party thrown by a few middle-aged women. Some are married, some are divorced, but all seem dissatisfied. When Ken serenades one of the sexually frustrated women and does a version of his striptease act, it doesn't come off as exploitative, it comes off as legit marriage counseling. And when the next morning, the guys find out that one of the women was the right "fit" for Big Dick Richie, the joy they express isn't typical macho chauvinism, but genuine affection for two people's happiness.
Overall, in fact, there is a feeling of good will in XXL that its predecessor often lacked. In that first film, a seediness was bubbling under the surface, primarily through the characters of Dallas and the Kid, to the point where Mike actually rejects that life and the promise of what's to come when the entire crew moves to Miami. When he rejoins the group in the sequel, a simple line of dialogue explains that Dallas bolted to England and took the Kid with him. It's almost treated as a throwaway, like the movie has no time to deal with such nonsense.
Pitch Perfect 2 similarly gets rid of a couple of narrative threads that no longer need to be explored, though one could say that it's thoroughly in the pursuit of nonsense. Beca's will-they-won't-they with Jesse was resolved at the end of the first film, as were her ongoing battles with the Bella's leader Aubrey. (It is a little sad though that because of this, Skyler Astin and Anna Camp--whose presence in the first movie I enjoyed greatly--were reduced to basically bit players.) Kay Cannon scripted both movies, but the second ups the ante with its pure absurdity. Cannon was writer on 30 Rock, and PP2 more closely resembles that show's rapid-fire, joke-a-minute style. It's appropriate for who she has in front of the camera performing her dialogue. Anyone who's seen Anna Kendrick in an interview or follows her on Twitter knows she's perfect as a sort of modern-day screwball comedienne. Rebel Wilson, Adam Devine, and newcomer Flula Borg also seem particularly tailored to this type of quippy humor, as does Keegan-Michael Key, who makes an extended cameo during the film. That doesn't even mention John Michael Higgins and Elizabeth Banks (who also makes her directorial debut here) as the series' version of Statler and Waldorf. All of this was there to some extent in the first installment, but here it's like the reins have been let loose.
If there's a narrative connective tissue between the two, or a theme addressed in both pictures, it's that to create, one must follow one's own path. And in doing so, rather than building upon what was developed in their first installments, they are rejecting them. In Magic Mike, Dallas created the dances, the personas the strippers used for the show. In XXL, Mike implores everybody, like the movie itself, to perform how they want to perform. Just as Richie throws out Mike's phone, Mike makes everyone throw their costumes out of the truck window. They all decide they have to come up with a new routine just a couple of days away from the convention.
Similarly, Beca's mashups and ear for synthesizing multiple songs into a single whole was her road to triumph in Pitch Perfect. But in PP2, when she gets a chance to give her demo to the record producer (played by Key) for whom she is interning, it's not enough. He tells her she needs an original idea. It's that idea--by producing an original song with newest member, Emily--that allows Beca to both impress her boss as a producer and win the competition against Das Sound Machine.
In an era of franchises, reboots, and sequels, it's easy for a piece of serialized filmmaking to spin its wheels in the mud (I'm looking directly at you, Marvel Cinematic Universe). But these two movies, in their oddly similar ways, show that it's possible to use an original property as a successful jumping off point. Sequels are often promoted as bigger and better. Sometimes bigger and better just means stripping down to essentials.