Our story begins with Naruto Shippuuden, when Naruto coming back to Konoha.
But something went wrong, and the story changed.
The world has changed.
It was changed by four shinobi, known as the Four Horsemen of the Apocalypse: Conquest, War, Famine and Death.
Nobody seems to know anything about them, except they're a great threat.
Shinobi had to make pretty big changes, because their only hope of survival was to work together.