Cast and characters
Winona Ryder as Joyce Byers, the mother of Will and Jonathan Byers. She is divorced from their father, Lonnie Byers. Protective and strong-willed, she becomes determined to find Will after he goes missing, convinced that his disappearance is paranormal in nature.
David Harbour as Jim Hopper, the chief of Hawkins Police Department. After his young daughter Sara died of cancer, Hopper divorced and lapsed into alcoholism. He becomes more responsible, helping Joyce investigate the truth behind Will's disappearance, and adopting Eleven as his daughter. He and Joyce have feelings for each other.
Finn Wolfhard as Mike Wheeler, middle child and the only son of Karen and Ted Wheeler, brother of Nancy and Holly, and one of Will Byers's three close friends. He is an intelligent and conscientious student and is committed to his friends. He develops romantic feelings for Eleven and later dates her.
Millie Bobby Brown as Jane "El" Hopper (née Ives) / Eleven, a girl with telepathic and psychokinetic abilities as a result of being one of Dr. Brenner's subjects from Hawkins National Laboratory. She escapes the lab and eventually becomes an adoptive daughter to Jim Hopper and takes his surname, and adjusts to living a normal life with the help of Mike (whom she later dates) and his friends.
Gaten Matarazzo as Dustin Henderson, one of Will Byers's friends. His cleidocranial dysplasia causes him to lisp. In the second season, he is proud of his new front teeth and is attracted to Max. In season three, he gets a girlfriend, Suzie, who he met at summer camp.
Caleb McLaughlin as Lucas Sinclair, one of Will's friends. He is wary of Eleven but later befriends her. In season two, he is one of Max's love interests and eventually becomes her boyfriend. In season four, he becomes more popular at school after joining the Hawkins High basketball team, which briefly puts him at odds with his regular friend group.
Natalia Dyer as Nancy Wheeler, daughter of Karen and Ted and older sister of Mike and Holly. Studious and rule-abiding, Nancy finds another side of herself while investigating Hawkins Lab and the death of her friend Barbara. In the first two seasons, she is the girlfriend of Steve Harrington, but breaks up with him and then dates Jonathan Byers. She is an aspiring journalist.
Charlie Heaton as Jonathan Byers, the older brother of Will Byers and the son of Joyce Byers. He is a quiet and kind-hearted teenager, an outsider at school, and an aspiring photographer. He is close with his mother and brother, and he becomes the boyfriend of Nancy Wheeler.
Cara Buono as Karen Wheeler (seasons 1–3 and 5; also starring: season 4), mother of Nancy, Mike, and Holly, who is mostly unaware of her children's activities for much of the series.
Matthew Modine as Dr. Martin Brenner (seasons 1 and 4; recurring: season 2), the scientist in charge of Hawkins Laboratory and training Eleven. Manipulative and remote, he and his team search for Eleven in season one after she escapes. He is referred to as "Papa" by Eleven. In season four, he returns to help Eleven regain her powers and protect her from the government agents hunting her down.
Noah Schnapp as Will Byers (seasons 2–5; also starring: season 1), the son of Joyce Byers and younger brother of Jonathan Byers. He is captured by a monster from the Upside Down in season one. He later develops a connection to the Upside Down and the Mind Flayer due to his capture. He struggles with his sexuality and unrequited feelings for Mike, and comes out as gay in season five.
Sadie Sink as Max Mayfield (seasons 2–5), Billy's younger stepsister and a tomboy who catches the attention of both Lucas and Dustin, eventually dating Lucas. In season four, she becomes one of the teens targeted by Vecna.
Joe Keery as Steve Harrington (seasons 2–5; also starring: season 1), a popular high school student and the boyfriend of Nancy Wheeler. He ostracizes Jonathan Byers but later befriends him. He and Nancy break up in season two but remain friends. He is known as the "babysitter" of the group, often left to look after the kids, particularly Dustin, with whom he forms a strong rapport.
Dacre Montgomery as Billy Hargrove (seasons 2–3; also starring: season 4), Max's violent, unpredictable, and abusive older stepbrother. He challenges Steve's popularity. In season three, he is controlled by the Mind Flayer and dies in the process.
Sean Astin as Bob Newby (season 2; guest: season 3), a former schoolmate of Joyce and Hopper who runs the Hawkins RadioShack. He is Joyce's boyfriend, putting him at odds with Hopper. He dies after being attacked by creatures from the Upside Down.
Paul Reiser as Dr. Sam Owens (seasons 2 and 4; guest: season 3), a Department of Energy executive who replaces Brenner as director of Hawkins Laboratory. He is committed to scientific research yet empathetic to the residents of Hawkins, and he helps Hopper adopt Eleven as his legal daughter. He returns with Brenner in season four to help Eleven regain her powers and to protect her from government agents hunting her.
Maya Hawke as Robin Buckley (seasons 3–5), Steve's co-worker at Starcourt Mall's Scoops Ahoy ice cream shop, who later comes out as a lesbian. Becoming close friends, she and Steve work together at Scoops Ahoy and later at Family Video. In season five, she begins dating her classmate Vickie, a volunteer nurse.
Priah Ferguson as Erica Sinclair (seasons 3–5; recurring: season 2), Lucas's younger sister who helps the group. She is very smart and has an avid interest in D&D.
Brett Gelman as Murray Bauman (seasons 4–5; also starring: seasons 2–3), a conspiracy theorist, private investigator, and old acquaintance of Hopper who assists Nancy and Jonathan, and later Hopper and Joyce.
Linda Hamilton as Dr. Kay (season 5), the sinister leader of the military unit dispatched to Hawkins after the opening of rifts to the Upside Down. She oversees a research base installed within the Upside Down itself.
Jamie Campbell Bower as Henry Creel / One / Vecna / Mr. Whatsit (season 5; also starring: season 4), a murderous psychic being from the Upside Down. Having attained supernatural abilities as a child, he murdered his family and was subsequently placed under Brenner's care. Flashbacks in season four reveal that an eight-year-old Eleven banished him to another dimension, where he was disfigured and joined the Mind Flayer's hive mind.
Nell Fisher (season 5) and Anniston and Tinsley Price (recurring: seasons 1–4) as Holly Wheeler, Nancy and Mike's younger sister and Karen's youngest child.
