Spoilers for Pacific Rim Uprising.
Pacific Rim Uprising is a belated sequel that is at once obsessed with the original movie and feels as if the creators didn't give it the full attention of a rewatch. By which we mean there's a lot of effort made to build on the mythology of Guillermo del Toro's 2013 Pacific Rim and retcon it to be a more suitable franchise building ground, and yet Uprising can't avoid making one gigantic plot hole bigger than the breach by which Level 5 Kaiju burst through.
That we have a Pacific Rim 2 is by itself remarkable. The first movie technically broke even (it just made double its $190 million budget, which per Hollywood math constitutes a success) but did so with a below average domestic taking and overall apathy around the project despite the del Toro faithful. However, when rights-holder Legendary was bought by the China-based Wanda Group, everything flipped and the sequel moved ahead - the original was a sizeable hit there and the franchise had great potential in the market.
All of that is important because it reveals the real angling of the sequel: something more global and forward-thinking. So while it is very much a rock 'em sock 'em adventure (one fight move even seems to be directly evoking those toy robots), efforts are made to craft a forward-propulsing mythology. And here's where the problem comes from.
This Page: The Precursor And Kaiju Motivations Change In Pacific Rim 2
What The Precursors Want In Pacific Rim
In Pacific Rim, any and all grander story motivation exists exclusively to enable mech-on-monster fights. Del Toro skips over much of the in-world logic to get to the existence of Jaeger's and Kaiju (including the logic of why robots are the first form of defence), but as the movie gets on does use a subplot with Charlie Day and Burn Gorman to provide some semblance of motivation.
This isn't just aimless monsters swanning out of the ocean to cause destruction but Stage 1 of a targeted world domination plan. Human-sized, extra-universe creatures known as the Precursors have built the Kaiju using bio-organic tech and send them over to other dimensions. The initial waves are hounds, checking the landscape and charting the world; next comes the exterminators, wiping out the indigenous population (in this case, humanity), before the creators themselves move over. Earth has been chosen due to its CO2-heavy atmosphere, a sly current affair tie-in that creates a more tangible global warming threat (it's alleged an invasion was tried at the time of the dinosaurs but the climate wasn't right).
We know all this thanks to the monster's neural network; Day's Newt and Gorman's Gottlieb drift with a Kaiju brain and due to the massive cross-species connection are able to read deep in the Precursor plot. Now, technically we only have their interpretation as a guide, but the way the film presents it is pretty resolute.
At the end, Pacific Rim did travel briefly over to the Anteverse and reveal a mysterious, day-glo land which seemed to confirm much of this, but that was really it. And it was all that was needed for a film whose best moment was a giant robot hitting a monster in the face with a boat.
What The Precursors Want In Uprising
On the surface, things are similar in Pacific Rim Uprising. The Precursor approach is altered due to the breach having been closed - much of the plot is about the Kaiju trying to use the neural network to manipulate humanity into reopening the rift between worlds - but once again they're trying to take over our world for themselves.
However, this time the methodology is actually different: rather than using Kaiju to clear out the decks, they're now living terraform-bombs. The blood inside the monsters is highly potent fuel - even used by Gottlieb to create Jaeger rockets - an incidental side note in the original but a key aspect of the Precursor plan this time; all Kaiju are on the same mission to throw themselves into active volcano Mount Fuji, starting a cataclysmic eruption that will fracture the entire pacific shelf and completely alter the Earth's atmosphere. It's stated explicitly this is to get the world ready for the Precursors.
Pacific Rim Uprising's plot hole should be immediately obvious: the goal of the Precursors has been changed from invasion to terraforming, with their decision to attack Earth due to its already suitable atmosphere completely changed. And while that could be explained away to misinterpretation on our part of their true motives, none of the proposed "clues" work.
- Pacific Rim Uprising (2018) release date: Mar 23, 2018