Following the conclusion of season four, we have a pretty good idea of who will be back for season five. Hawke, Harbour, Winona Ryder, Millie Bobby Brown, Finn Wolfhard, Gaten Matarazzo, Caleb McLaughlin, Natalia Dyer, Charlie Heaton, Priah Ferguson, Schnapp, and Joe Keery all made it out of the season alive and should return. Sink's Max went through some major trauma in season four, but it seems she'll be back, too. Jamie Bower Campbell will also be back as Vecna, and it's likely Eduardo Franco will still be around as Argyle. But if fan favorite Quinn returns as Eddie Munson, he'll have to communicate from the afterlife.
Meanwhile, in an IndieWire interview, published on 11 Aug., 2022, the Duffer brothers told the publication, "We're doing our best to resist [adding new characters] for Season 5." The temptation apparently won out, as Linda Hamilton was announced as joining the cast on 17 June.