The trailer is out for Season 5 of "Teen Wolf," and creators are touting it as the "darkest" season ever.

According to HollywoodLife, all the cast's most popular stars are back, with each of them, from Scott (Tyler Posey), Stiles (Dylan O'Brien), Lydia (Holland Roden), Malia (Shelley Hennig) and Kira (Arden Cho), all wearing the look of someone "really, really worried."

In addition, the teaser for the new season features a promo reading, "The doctor will see you now," with a voiceover from Dr. Deaton (Seth Gilliam) adding, "The rules have changed."

HollywoodLife also reports Posey recently revealed more will happen between Scott and Kira, much of which stems from his apparent maturation.

"I can't wait for people to see," he said. "He's really calculated and calm and has been there and has gone through all these scenarios and situations like a calm adult. He's experimenting. I mean, I experiment with new ideologies all the time. I'm still growing up as an individual and Scott is as well, and he's like, 'You know what, I'm gonna handle this a little more maturely and calculated and calm and really be zen about things.' And have everybody relax."

TVLine reports, while the promo is less than a minute long, it "gives us our first look at the entire pack -- Scott, Stiles, Lydia, Malia and Liam, bracing for the arrival of a heinous new enemy, one that appears to have an affinity for torture."

Of the new season, executive producer Jeff Davis recently told TVLine that it will focus on the group during their senior year of school and the change from childhood to adulthood.

"But as always, we bring in some new mysteries and new monsters. I think this season is very much about the line between science and supernatural," he said.

"Teen Wolf" Season 5 is expected to consist of 20 episodes, nearly double the number of airings for last season.

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