Will Byers is a recurring character in the first season, and a main character in the second season. He was abducted by a terrifying monster and taken into an alternate dimension. His time in the Upside Down left him with a mysterious connection to the alternate realm.
Mike Wheeler is a major character in both seasons. When his friend Will went missing, during the search, he and his friends found a strange little girl called Eleven. Mike and Eleven formed a strong bold.
Eleven (Jane Hopper) is a major character in both seasons. She was kidnapped and raised in Hawkins National Laboratory where she was experimented on for her inherited psychokinetic abilities.
Lucas Sinclair is a major character in both seasons. He is one of the best friends of Mike Wheeler, Dustin Henderson, and Will Byers. When this new girl arrived, Max, he grew a bond with her, eventually becoming his love interest.
Maxine Mayfield, better known as Max, is a new and main characterin the second season. She moved to Hawkins after her mom married Neil Hargrove.
Dustin Henderson is a major character in both seasons. He is best friends with Mike Wheeler, Lucas Sinclair, and Will Byers. In the second season, he raised D’Artagnan that he later discovered it was a juvenile Demogorgon.
Jonathan Byers is a major character in both seasons. He is the older brother of Will Byers. His life was turned upside down following the disappearance of his younger brother.
Nancy Wheeler is a major character in both seasons. She is the older sister of Mike Wheeler. Her life was turned upside down following the disappearance of her best friend Barbara Holland.
Steve Harrington is a recurring character in the first season and a main character in the second season. He is friends with the bullies Tommy H. and Carol of Hawkins High School. He is dating the brainy and innocent Nancy Wheeler.
Barbara Holland, better known as Barb, is a recurring character in the first season. She was best friends with Nancy Wheeler. During the first season, she mysteriously vanishes, which leads Nancy and Jonathan to investigate her disappearance.
Billy Hargrove is a main character and a secondary antagonist in the second season. He is Max’s stepbrother, he moved to Hawkins when his dad married Susan Mayfield.
Eight (Kali Prasad) is a recurring character introduced in the second season. Kali was one of several test subjects experimented upon at Hawkins Lab. She has the power to make people see things that are not really happening.
Joyce Byers is a major character in both seasons. She is the poor single mother of Will and Jonathan Byers, she works as a retail clerk and relies on help from her eldest to make ends meet.
Karen Wheeler is a major character in both seasons. She is the wife of Ted Wheeler and the mother of Nancy, Mike, and Holly Wheeler.
Jim Hopper is a major character of both seasons. Hopper is the Chief of Police in the small, sleepy town of Hawkins, where he lives out a carefree existence, yet he is haunted by a troubled past.
Bob Newby is Joyce’s new boyfriend. He often hangs around Joyce’s house. Bob is killed by a Demo-dog after saving Will, Hopper, Joyce, Mike and Dr.Owens from the Hawkins Lab.
Sam Owens (Dr.Owens) is a major character and an introduced character in the second season. He is one of the doctors in the Hawkins Lab.
Martin Brenner is a major character in the first season. Brenner is a senior research scientist and the director of Hawkins Lab.
Scott Clarke is a recurring character in the first and second season. He is a science teacher of the boys in Hawkins Middle School.