Shaymin, a small Gratitude Pokémon that blooms flowers wherever it goes, gets caught in a clash between the Legendary Pokémon Giratina and Dialga after Giratina drags Dialga into the parallel Reverse World. Ash, Dawn, and Brock take Shaymin in and try to keep it safe as Team Rocket and Zero, the former assistant of a scientist who once studied Giratina, pursue the Pokémon for their own ends. This manga adapts the eleventh Pokémon feature film.