'Stranger Things' season 5 will need to have a time jump, according to the Duffer brothers

• Ross Duffer said that he's "sure" that "Stranger Things" season five will include a time jump.
• The Netflix series premiered in 2016, and its young cast members have aged past their characters.

The Duffer brothers said that they were "sure" they would need to do a time skip for the fifth and final season of "Stranger Things," given the aging of the show's young cast members.

"Stranger Things" season four, part one premiered on May 27 on Netflix, bringing an end to the show's nearly three-year hiatus. The supernatural series, which is one of the streaming platform's most popular, premiered in 2016 when its youngest cast members were in their pre-teen years.

Six years later, the discrepancy between their ages and those of their characters' has become more noticeable. Millie Bobby Brown is approximately four years older than her character, Eleven, while stars like Caleb McLaughlin and Sadie Sink are approximately six years older than their characters Lucas and Max in the show.

"I'm sure we will do a time jump," Ross Duffer, who cocreated the series and serves as showrunner and executive producer alongside his brother, Matt Duffer, told TV Line of the show's fifth season. He added that "ideally" seasons four and five would have filmed back to back, "but there was just no feasible way to do that."

In February, Netflix revealed that season five of the series would be its last, finally bringing to an end the story of Eleven, played by Millie Bobby Brown, and her conflict against the monsters of the Upside Down alongside her friends.

The showrunning team said in a letter to fans at the time of the announcement that they had planned out the full story of "Stranger Things" seven years previous. Matt Duffer told TV Line that while he couldn't say when shooting would start for season five, it was already "pretty well mapped out."

Before hopping into the writers room for season five, however, Ross Duffer told TV Line that they had more pressing concerns at the moment — namely, the second part of season four that's set to premiere on Netflix on July 1.

"Believe it or not, we're still working on season four," he said. "We're trying to finish the final two episodes, they're so massive."