Winona Ryder as Joyce Byers[3] David Harbour as Jim Hopper[3] Finn Wolfhard as Mike Wheeler[4] Millie Bobby Brown[4] as Eleven ("El") Gaten Matarazzo as Dustin Henderson[4] Caleb McLaughlin as Lucas Sinclair[4] Natalia Dyer as Nancy Wheeler[4] Charlie Heaton as Jonathan Byers[4] Cara Buono as Karen Wheeler[5] Matthew Modine as Martin Brenner[6]