Will Byers relives his nightmare in the Upside Down in ‘Stranger Things 5’ first five minutes

Netflix has dropped the opening five minutes of “Stranger Things 5,” giving fans a haunting look back at Will Byers’ first days in the Upside Down.

The clip opened with a de-aged 12-year-old Will (Noah Schnapp), trembling inside the Upside Down version of Castle Byers and softly singing “Should I Stay or Should I Go” to himself.

But the moment is cut short when guttural noises signal the arrival of a Demogorgon, which smashes into the fort.

Will flees into the forest, climbing a tree to escape. He leaps toward another branch but falls hard, losing consciousness, and the Demogorgon drags him to the Upside Down’s Hawkins Library, where Vecna emerges from the shadows.

Using vines to pin Will to a wall, Vecna injects an unknown substance into his body through a tentacle attached to his mouth.

“At long last, we can begin,” Vecna says before whispering, “You and I, we are going to do such beautiful things together, William.”

"Stranger Things" Season 5 has been teased to be the biggest and darkest season of the show yet. The cast and crew kicked off production in January last year.

In the official teaser released in July, the characters were shown preparing as they work to battle the Demogorgons and Vecna.

Season 5 will be released in three parts, with Volume One premiering on November 26. Volume Two will follow on Christmas Day, and the finale will be on New Year's Eve. — Carby Basina/LA, GMA Integrated News