Season 3 of Netflix's hit show Stranger Things has officially wrapped filming. The series became an overnight sensation after it debuted on the streaming service in 2016, and after the first two seasons received positive reviews, as well as a passionate fan following, the upcoming third season will revisit the science fiction-based horrors of Hawkins, Indiana in the summer of 2019.

The first season of Stranger Things revolved around the disappearance of Will Byers (Noah Schnapp), the mysterious young girl named Eleven (Millie Bobby Brown), and Will's friends (Finn Wolfhard, Caleb McLaughlin, and Gaten Matarazzo) who are hell bent on finding him. The second season further developed Eleven's powers, while also introducing a new threat known as the Mind Flayer. Now, the third season - which has been described as Eleven's coming of age story - will be even darker and more action-packed than previous seasons, and it'll return to the first season's summer premiere slot.

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According to several Instagram posts from various cast members on Stranger Things, filming has officially wrapped for season 3. David Harbour, who plays Chief Jim Hopper, shared an image of himself wearing a Gary's Plumbing and Heating hat, not only covering his eyes, but drawing attention to his mustache (which he teases won't last very much longer). Brown also posted two photos on her personal Instagram account, simply captioning her post: "that's a wrap". Likewise, Schnapp shared Brown's photo with a similar caption.

The third season of Stranger Things is no doubt a highly anticipated entry to the series, and producer Shawn Levy has previously commented that season 3 will be the most ambitious season yet. Along with the cast members from the first two seasons, Ethan Hawke and Uma Thurman's daughter Maya Hawke has joined the cast, along with Cary Elwes and Jake Busey. Francesca Reale has also been cast in the key role of Heather, a lifeguard at the Hawkins community pool.

While it might seem concerning that Brown's Instagram photos say "One More Time" at the bottom, fans shouldn't be worried about season 3 potentially being the last in the series. Levy has already confirmed that season 4 is "definitely happening." That said, those words are certainly grounds for speculation, and given that Brown had posted pictures of herself with Schnapp and Sadie Sink, who plays Max Mayfield, with the "One More Time" caption, some might speculate that one, two, or all three of the characters may not survive season 3. That being said, the conclusion of filming for season 3 was likely an emotional period for the young actors, so these images may well have no connection to next season's storyline at all. And, no matter where the pre-season theories lead, most fans will agree that the emotional reaction of the young cast is just as devastating as Harbour saying goodbye to his character's trademark mustache.

More: Telltale's Canceled Stranger Things Game Footage Leaks Online

Stranger Things season 3 will premiere Summer 2019 on Netflix.

Source: David HarbourMillie Bobby Brown