'Stranger Things' series finale trailer teases final battle against Vecna

Netflix has released the trailer for the last episode in Stranger Things' fifth and final season, teasing the end of the Duffer Brothers' hit series after a decade-long run. We've come a long way since the vanishing of Will Byers (Noah Schnapp) in November 1983. 

It's been four years since Mike (Finn Wolfhard), Dustin (Gaten Matarazzo), and Lucas (Caleb McLaughlin) first encountered Eleven (Millie Bobby Brown) and the Upside Down, and now their battle against Vecna (Jamie Campbell Bower) is finally coming to a head. 

Having learned more about the Upside Down's true nature and Venca's ultimate plan, the Hawkins teens are on a mission to stop him once and for all, fighting alongside allies Joyce (Winona Ryder), Hopper (David Harbour), Max (Sadie Sink), Nancy (Natalia Dyer), Jonathan (Charlie Heaton), Steve (Joe Keery), and Robin (Maya Hawke). It won't be an easy task though, and victory may require painful sacrifices.

The series finale of Stranger Things premieres Dec. 31 at 8 p.m. ET / 5 p.m. PT on Netflix.