Set ten years after the events in The Phantom Menace, the galaxy is on the brink of civil war, with thousands of planetary systems threatening to secede from the Galactic Republic. After Senator Padmé Amidala evades an assassination attempt, Jedi apprentice Anakin Skywalker becomes her protector, while his mentor Obi-Wan Kenobi investigates the attempt on her life. Soon, the trio witness the onset of a new threat to the galaxy, the Clone Wars.

References:
https://en.wikipedia.org/wiki/Star_Wars:_Episode_II_%E2%80%93_Attack_of_the_Clones