Watch the official "Becoming Vecna" featurette for the Netflix horror series Stranger Things Season 4 Volume 2. It stars Winona Ryder, David Harbour, Finn Wolfhard, Millie Bobby Brown, Sadie Sink, Gaten Matarazzo, Caleb McLaughlin, Natalia Dyer, Jamie Campbell Bower, Charlie Heaton, Matthew Modine and Cara Buono.