Giratina first appeared in the 11th Pokémon movie, Giratina and the Sky Warrior. In beginning of the movie, Giratina's home world, the Reverse World, was polluted with black, poisonous clouds due to Dialga and Palkia's deadly battle in Alamos Town from the previous movie. This disturbance angered Giratina so much that it decided to get revenge on both of them by battling with Dialga first. When Dialga stopped at a lake to get a drink of water, Giratina lured it through the portal and attempts to engage it in a battle. However, thanks to Shaymin, who unexpectedly stowed away on Dialga's tail, used its Seed Flare move to give Dialga a chance for it to escape and return to its own dimension. Giratina tried to follow it, but it ended up getting trapped in the time loop, which causes it to become unable to move into the real world. Giratina decided to capture Shaymin so it could use Seed Flare again to create a hole in the real world, which in fact shattered Dialga's time loop. Later on in the movie, a greedy and selfish man named Zero, who is planning to use Giratina's abilities to rule the Reverse World, captures Giratina and absorbed most of its powers. Unfortunately, Ash and his friends snuck into Zero's airship and freed Giratina from its prison. After that, Giratina nearly dies from the energy drainage of its powers but was healed by Shaymin's Aromatherapy. In the climax of the film, Giratina assisted Ash, Pikachu and Shaymin to battle Zero and put a stop to his evil plans once and for all. After the Reverse World was saved from Zero, Giratina thanked Ash and his friends for their help and goes off to continue its search for Dialga.
Arceus and the Jewel of Life
Giratina made its second and final appearance in Arceus and the Jewel of Life. After Dialga saved Pikachu and Piplup from being sucked into a deadly spacial distortion, Giratina appears and ambushes Dialga. Sheena tried to communicate with it by reaching into its heart, but due to its anger towards Dialga it was filled with rage. Ash pleaded it to stop and Giratina, who recognized him as the same person who save its life and helped save the Reverse World from Zero, calmed down. Once Giratina stopped attacking, Sheena reached into its heart and told it to return to its dimension. Later, when Arceus came and started destroying Michina Town, Giratina assisted Dialga and Palkia in protecting Ash and his friends from Arceus's attacks. Although it was injured, Giratina was healed by Arceus after the timeline was changed and returned to the Reverse World where it could live in peace once more.