If you meant the movie series directed by Guillermo del Toro, here is the watch order and world lore.
"Pacific Rim" was released on July 12, 2013, and grossed over $411 million worldwide. The film received positive reviews from critics, with an 81% approval rating on Rotten Tomatoes. The film was praised for its: pacific rim -2013
He is recruited by (Idris Elba), the weary, commanding leader of the last remaining Jaeger base in Hong Kong—the Shatterdome . Pentecost plans one final, desperate assault: send all remaining Jaegers through a fissure in the ocean floor to the aliens' dimension (the Anteverse ) and detonate their nuclear cores, collapsing the breach. If you meant the movie series directed by