Ash and his friends arrive in Eterna City, where Dawn is preparing to participate in the Pokémon Contest. There, they meet a woman named Alice who pilots a hot-air balloon, her childhood friend Tonio, and Baron Alberto. Baron Alberto believes that the Dark-type Pokémon Darkrai, which resides in the town's garden, is responsible for the recent destruction in the city and is determined to defeat it. However, Tonio has a different perspective. He detects an abnormal shockwave above Eterna City, caused by the legendary Pokémon Dialga, who controls time, and Palkia, who controls space, battling in the dimensional rift. Darkrai's attacks are actually an effort to keep them away from the town. As the conflict between the two deities intensifies, a spatial rift finally appears above Eterna City's famous landmark, the "Tower of Time and Space," and the battleground shifts to the city itself. How will Ash and his friends stop this crisis? And how will the misunderstandings surrounding Darkrai be resolved? An intense battle across time and space is about to unfold!