LOS ANGELES (Reuters) – A year has passed since a supernatural demon terrorized the town of Hawkins, Indiana, but as Netflix’s hit 1980s science fiction series “Stranger Things” returns for a second season on Friday, life has not returned to normal for the unlikely heroes.

The adults and teenagers of “Stranger Things 2” wrestle emotionally with the events of the first season: a town boy’s disappearance, a death, a mysterious girl with superpowers and a decaying parallel universe called the Upside Down.

“We wanted that trauma to really run through the entire season so it’s about these characters confronting the horrors,” said Matt Duffer, one half of the Duffer Brothers, the twins who created the show.

All nine episodes of “Stranger Things 2” will be released on Friday.

At the center of the show are its young teenage breakout stars. Will Byers (Noah Schnapp) suffers worsening visions of the Upside Down after being rescued, forcing his friends to try to find a way to defeat the demon known as Demogorgon.

Eleven, the innocent, tormented young girl with superpowers played by Emmy-nominated 13-year-old Millie Bobby Brown, is believed dead and is in hiding, staying with the town’s police chief, Jim Hopper. Frustrated at being kept away from her friends, Eleven clashes with Hopper (David Harbour) and embarks on a mission to find her mother and finally find a home.

“We wanted (Eleven) to go through her own journey in a way that was much more personal to her and wasn’t tied to the boys,” Matt Duffer said. “We wanted her to go through a journey of self-discovery without the help of anyone else.”

“Stranger Things” has become a phenomenon for Netflix Inc, landing Emmy wins and drawing a cadre of obsessed fans who launched a viral online campaign, #JusticeForBarb, sparked by the gruesome demise of supporting character Barb Holland.

The second season ramps up the quest to bring closure to her death while introducing new characters and expanding the story geographically.

The Duffers said they anticipate five seasons to bring “Stranger Things” to a conclusion.

“It was important to us this season to start to move out of Hawkins and to introduce this world,” said Ross Duffer.

“It’s such a fine line and it’s difficult and obviously sequels always feel this way because people want some of the same – that’s why they liked it in the first place – but you don’t want to just go in circles,” he added.