After the overwhelming success of the Netflix original series "Stranger Things" season 1, co-creator, Matt Duffer, is now saying that season 2 will be a little bit different, a little bit darker.

The show announced in January that there will be another season to look forward to this year.

The official trailer for the show's season 2 gives little detail as to what people can expect. The only thing that's crystal clear for now is that "the world is turning upside down," or so the teaser says.

Twin brothers Ross and Matt Duffer, the creators of this show, assure that they have created a season 2 that is equally as compelling as season 1. "It's a balance of the comfort you're familiar with but then trying to take it in new directions," Ross told Entertainment Weekly in an interview.

The season 1 of this science fiction/thriller drama series was critically acclaimed. It even took the Screen Actors Guild Awards for Outstanding Performance by an Ensemble in a Drama Series. Its young, budding cast became popular worldwide, especially online.

"People love the characters so much, and they have such an emotional response," David Harbour, who plays Sheriff Hopper, told the same publication.

The Netflix synopsis for "Stranger Things" season 1 reads, "When a young boy vanishes, a small town uncovers a mystery involving secret experiments, terrifying supernatural forces and one strange little girl."

"They never expected Barb to be a hit — they never expected the show to be as successful," Gatten Matarrazo, who plays Dustin, said in the same interview. Barb is short for Barbara (Shannon Purser) whose death in the series became a trending topic online using the hashtag #JusticeForBarb.

The now famous and award-winning young ensemble of the "Stranger Things" also include Millie Bobby Brown as Eleven, Finn Wolfhard as Mike, Noah Schnapp as Will, and Caleb McLaughlin as Lucas.

Award-winning actress Winona Ryder also stars as Will's mom, Joyce.

There will be nine episodes for season 2, the titles of which were already announced by Netflix: "Madmax," "The Boy Who Came Back to Life," "The Pumpkin Patch," "The Palace," "The Storm," "The Pollywog," "The Secret Cabin," "The Brain," and "The Lost Brother."

"Stranger Things" season 2 will come out on Halloween, Oct. 31, on Netflix.