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.

With El and Max looking for Billy, Will declares a day without girls. Steve and Dustin go on a stakeout, and Joyce and Hopper return to Hawkins Lab.