I remember -nothing- from last season of AOT
Guy named Kenny shows up, he's the guy that raised Levi and made him a badass.
Krista/Historia reunites with her dad who is the real king Rod.
The truth about royalty is exposed and the people in the wall revolt.
Rod tries to make Historia eat Eren so she can get her half-sister's powers. She refuses.
He turns into a freaky Titan and tries to destroy everything. Historia stops him. She's crowned the queen.
Now begins the quest to regain the outer walls, and Reiner & Bertholt are there.