S5E2 · Chapter Two: The Vanishing of Holly Wheeler

Complete story — includes the ending

The Demogorgon attacks and severely injures Mike and Nancy's parents, Karen and Ted, before disappearing with Holly to the Upside Down. Eleven follows the Demogorgon through a gate into the Upside Down and finds Hopper. The two then search for Holly until they encounter a giant wall surrounding the edge of Hawkins. Jonathan accuses Steve of competing for Nancy's attention before a bloodied Dustin finds them, while Lucas continues tending to a comatose Max in hopes she will wake up. As Karen and Ted remain hospitalized, Nancy and Mike theorize that "Mr. Whatsit", Holly's imaginary friend, may be real and involved in Holly's disappearance. Robin proposes using Will's telepathic link to Vecna's hive mind to track Holly in the Upside Down. Karen informs Nancy and Mike that Mr. Whatsit's first name is Henry, whom they realize is Vecna's human form, Henry Creel. Will discovers that his earlier visions were actually from Henry's point of view as he stalked Holly, realizing he can know Henry's targets before they are taken.