Nancy and Jonathan swap conspiracy theories with a new ally as Eleven searches for someone from her past. “Bob the Brain” tackles a difficult problem.

Behind the Iron Curtain, a risky rescue mission gets underway. The California crew seeks help from a hacker. Steve takes one for the team.

As Hopper braces to battle a monster, Dustin dissects Vecna's motives — and decodes a message from beyond. El finds strength in a distant memory.