Satoshi and Pikachu have reached Lumiose City in the renowned Kalos region to catch more Pokémon and press on with their journey to become the very best. Meanwhile, a genius inventor named Citron and his younger sister Eureka are wandering the city when they cross paths with Satoshi, who promptly challenges them to a battle. However, they are soon drawn into a perilous situation when Team Rocket, having followed Satoshi into Kalos, causes a Gaburias to rampage through the city. Far away in the quiet Vaniville Town, a young girl named Serena endures daily Sihorn riding practice at her mother's insistence; her mother is a professional Sihorn racer. After practice, she watches the events unfolding in Miare City on television and recognizes a boy from her childhood. Having left a significant impact on her life, the sight of him stirs in her a desire to meet him again; so, Serena sets off for Miare City, determined to find the boy from her past. Pokemon XY follows the group as they travel throughout Kalos in pursuit of their ambitions—Satoshi challenging Pokémon gyms, Citron learning from Satoshi, and Serena searching for what exactly her dream is. Along the way, they meet new friends, face new rivals, and continue to thwart Team Rocket's schemes, all the while discovering a little about the mysteries of mega evolution.