"Stranger Things" Season 4 is divided into two main storylines: one in Hawkins, Indiana, and the other in various locations including California and Russia.
Hawkins:
Back in Hawkins, a series of gruesome murders begins to plague the town. These killings are linked to a new and terrifying entity from the Upside Down known as Vecna. Vecna targets troubled teens, preying on their traumas and fears to kill them, which allows him to open gates to the Upside Down. As the deaths escalate, Mike, Dustin, Lucas, Max, and their new friend Eddie Munson, the leader of the Hellfire Club, band together to investigate. Max becomes one of Vecna's targets due to her grief over her brother Billy's death. The group discovers that music can temporarily protect Vecna's victims, using this knowledge to save Max.
California and Russia:
Meanwhile, in California, Eleven struggles with being bullied at her new school and coping with the loss of her powers. Mike visits her during spring break, and together with Will and Jonathan, they become entangled in a government conspiracy. Dr. Sam Owens and Dr. Martin Brenner return to help Eleven regain her powers to combat the new threat in Hawkins.
In Russia, Joyce and Murray Bauman learn that Hopper is alive and being held in a Soviet prison. They embark on a dangerous mission to rescue him, which involves battling Demogorgons the Russians are experimenting on. Their rescue operation is perilous but successful, reuniting Joyce and Hopper.
Final Confrontation:
As the separate storylines converge, the group in Hawkins attempts to confront Vecna directly. Eleven, after regaining her powers, enters a sensory deprivation tank to project herself into the Upside Down to help her friends. They uncover that Vecna is actually Henry Creel, a former human who was the first child subjected to Brenner's experiments and who became the powerful being known as One. He was banished to the Upside Down by Eleven years earlier, where he transformed into Vecna.
The season culminates in a fierce battle where Eleven fights Vecna in the mental plane while her friends physically attack him in the Upside Down. Despite their efforts, Vecna's plan partially succeeds, opening multiple gates and causing catastrophic damage to Hawkins.
The season ends on a somber note, with the town in ruins and the characters preparing for an even larger battle ahead, as the barrier between the real world and the Upside Down continues to weaken, setting the stage for the final showdown in the series' next season.
