'Stranger Things' season 2 spoilers: Wil Byers' friends spotted biking in Hawkins

The cameras are now rolling for the sophomore season of Netflix's runaway hit "Stranger Things."

The Sun recently spotted young stars Finn Wolfhard, Gaten Matarazzo, and Caleb McLaughlin on the set of "Stranger Things" season 2 as they reprise their roles as Mike Wheeler, Dustin Henderson and Lucas Sinclair, respectively.

The child actors were seen riding their signature bikes as they drive around the streets of the fictional town of Hawkins, Indiana. There are other photos showing Matarazzo and McLaughlin talking with each other while filming for another scene in the series.

In season 1, the three boys portrayed the roles of Wil Byers' (Noah Schnapp) closest friends who tried to find a way to bring him back from the Upside Down with the help of Eleven (Millie Bobby Brown), a strange girl with psychokinetic abilities. Yet Wil was noticeably missing in the behind-the-scene photos for season 2.

"Stranger Things" became a surprise hit for Netflix in summer 2016. Even the streaming service provider's content chief Ted Sarandos admitted that he never expected the series to become a phenomenal pop culture hit.

"I knew it was something special," Sarandos said during the UBS Global Media and Communications Conference as reported by Decider. "The Duffer brothers, who created the show, said they had pitched it 19 times before they came to Netflix. Their pitch was great and they had never done anything except for a small movie and a couple of episodes of a show called Wayward Pines, so there wasn't a lot to go on in terms of their track record."

While the plot of "Stranger Things" season 2 remains a mystery, series creators Matt and Ross Duffer announced that several new characters will be introduced next season. The list includes Sadie Sink as Max, and Dacre Montgomery as her older stepbrother Billy. They will also be joined by Sean Astin as Hawkins Radio Shack manager Bob Newby, Paul Reiser as Department of Energy executive named Owens, Linnea Bethelsen as an emotionally damaged woman named Roman, as well as Brett Gelman as a former journalist named Murray Bauman.

The second season of "Stranger Things" is expected to be released by Netflix in 2017.