
Season 5 will need to address many unresolved issues, such as whether Stranger Things has a strategy for Argyle and whether Steve Harrington will be able to withstand another fight in the Upside-Down. The fate of these supporting characters is less significant than that of Stranger Things's forgotten hero, though. Will Byers has been at the centre of Stranger Things ever since the premiere episode. Season 1's main plot was around his kidnapping, Season 2's main plot revolved around his possession, and Season 4 finally allowed Will some stage time and developed his wounded character. Sadly, this might be a result of Will's death in Stranger Things season 5.
Vecna, the evil ruler of the Upside-Down, was the primary enemy in Stranger Things season 4, despite the army causing Eleven some trouble. Vecna's history revealed that he was the creator of the Upside-Down, with the hitherto invisible puppeteer planning the events of Stranger Things up to this point so that he could someday confront Eleven again after losing a psychic battle against her years before.