Finished the Soul Society saga, Ichigo and the other protagonists managed to save Rukia Kuchiki. Although she had to part ways with her, everything was handled in the best possible way considering Captain Aizen's betrayal. But in the next saga, the real war begins: Here is the Summary of Bleach's Arrancar saga.
After successfully returning to Karakura, Ichigo and the others resume peaceful lives, at least on the surface. In reality, the protagonist must improve and learn to control his powers, especially the hollow ones. To help him, Shinji Hirako will be there, one of the vizards, Shinigami who can use hollow powers to become stronger. Almost simultaneously there is the first invasion of the arrancars in Bleach: Ulquiorra and Yammi's arrival in Karakurah wreaks havocbut this landing is very short.
Ichigo continues to train while Sosuke Aizen refines his plans in Hueco Mundo. This whole period of apparent calm is just a prelude to the second arrancar invasion, this time facing fierce resistance from some shinigami. After many fights and clashes between Ikkaku Madarame, Hitsugaya, Rangiku and especially Ichigo Kurosaki against Grimmjow Jaegerjacques, it turns out that the former captain's goal was actually Aizen kidnap Inoue Orihimewhich will follow Ulquiorra in Hueco Mundo.
After discovering this, the human protagonists prepare to rescue the girl with an invasion of Hueco Mundo. there Bleach Arrancar Saga ends with chapter 241 of the manga and episode 141 of the anime.