Terror reigns in the food court when the Mind Flayer comes to collect. But down below, in the dark, the future of the world is at stake.

With time running out — and an assassin close behind — Hopper’s crew races back to Hawkins, where El and the kids are preparing for war.

Dr. Alexei reveals what the Russians have been building, and Eleven sees where Billy has been. Dustin and Erica stage a daring rescue.

Strange surprises lurk inside an old farmhouse and deep beneath the Starcourt Mall. Meanwhile, the Mind Flayer is gathering strength.

A code red brings the gang back together to face a frighteningly familiar evil. Karen urges Nancy to keep digging, and Robin finds a useful map.