This is the first time Team Rocket is seen working alongside the main villain of the film.
One idea for the film originally had Raikou, a counterpart to Suicune, appear instead. Suicune was added when it was determined the film would involve a lake.
This movie is an example of the grandfather paradox.
A Celebi Pokemon trading card was given out in theaters in the USA. Another card of Suicune came with the home video release.
This is the first movie in which a Pokémon evolves (Metapod into Butterfree).