Just because Stranger Things is coming to an end doesn't mean season 5 didn't find a way to expand - and recast - with some new characters. Stranger Things, which premiered in 2016, is set to conclude with its fifth and final season. While the stakes have never been higher as the group prepares for one final battle with Vecna (Jamie Campbell Bower), the first part of the final season took time to reintroduce Mike (Finn Wolfhard) and Nancy's (Natalia Dyer) sister, Eleven's (Millie Bobby Brown) surrogate sibling and more.