Belladona was seen in the first film as a spirit trapped in the realm of Obsidian, along with her sisters, Lysliss and Tarma. They command their servant, Mandragora, throughout the movie, targeting Bloom primarily.
Belladona appeared in the second movie with her sisters after their escape from the realm of Obsidian. Assisted by the Trix, the Ancestral Witches cause the negative part of the Tree of Life to take over the whole of it, annihilating its positive part with the exception of the positive magic that is contained in a pollen in Havram .
Belladona: (to Icy) "YOU STUPID WITCH!!! Destroying the sapling releases all of the positive magic at once!"
Belladonna is an Italian word meaning Beautiful Lady, as well as the name for the Deadly Nightshade plant, which according to popular folklore was used by witches to make ointments that helped them to fly to witch gatherings.