Nancy is with Vecna and learns that it's Peter and that he killed his family.

Peter was the Creel son.

Brenner wanted to copy him and make more, explaining the need for 11 in the first place.

He wants to kill Nancy and Eleven and everyone else.

Nancy tries to escape, but it's not happening.

She sets off on a mission.

Back in the lab, Peter tells Eleven to wait and he'll find a way to save them both.

This does not sit well with her and she goes into the lab to find him massacring everyone.

He tries to kill her, but she gets a memory of her mother and her being brought into the world.

Eleven gets up the courage to defeat him.

Hopper and Antonov fight a Demogorgon that's killing everyone in the prison.

Joyce and Murray barge their way in and save Hopper, leading to an emotional resolution.

Mike and the others make their way to Suzie's and learn that the computer is the Nina project and it's located in Nevada.

They decide to go there to save Eleven's life.