After some casting shake ups, Netflix's original series Sex Education has finally begun filming Season 4! Show lead Asa Butterfield shared the news via Twitter, posting a photo of himself by the trailers, with the caption "Guess who's back." His fellow co-star, Alistair Petrie, responded with a photo of himself in a similar location, caption reading "Give us a clue."

In Sex Education, viewers primarily follow Otis Milburn (Butterfield), an awkward teenager on several fronts not helped by the fact that his mother Jean (Gillian Anderson) is a sex therapist. When Otis accidentally provides sex advice to one of his peers, he teams up with fellow student Maeve (Emma Mackey) to run an underground sex therapy clinic at school. However, by the show's most recent Season 3, someone else has co-opted the clinic and is handing out bogus advice. Moordale Secondary also hired a new head teacher, Hope (Jemima Kirke), who planned to fix the school's image through a number of policy changes.

Season 3 left Otis and the gang a lot to contend with heading into its fourth season. The most pressing issue is that Moordale Secondary's students no longer have a school to return to. As Season 3 ended, Hope was fired, and developers bought the school, leaving students to seek education elsewhere. One student relatively unaffected by the upheaval is Maeve, who accepted a major opportunity to study abroad in the U.S. Unfortunately for viewers rooting for Otis and Maeve to get together, the notion was halted as the two said farewell (for now). Meanwhile, after some scary complications, Jean gave birth to her baby! While everyone initially believed Jakob (Mikael Persbrandt) was the father, Jean dropped the bombshell that the father is someone else.

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Image via Netflix

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Though little is known plot-wise about Season 4, viewers can expect some of the major threads left in Season 3's wake to continue. A few cast members will also be notably absent in the new season. Due to a blend of personal and creative decisions, former cast members Patricia Allison (Ola), Tanya Reynolds (Lily), Rakhee Thakrar (Emily Sands), and Simone Ashley (Olivia) will not return to the series. New faces are expected to join the upcoming season, though no casting announcements have been made.

Along with Butterfield and Petrie, Ncuti Gatwa was recently confirmed to reprise his role as Eric. Additional cast still expected to return are Mackey, Anderson, Connor Swindells, Aimee Lou Wood, and Kedar Williams-Stirling. Creator, writer, and executive producer Laurie Nunn will also return for Season 4.

Sex Education Season 4 does not yet have a release date. Seasons 1-3 are streaming now on Netflix. Check out the Season 3 bloopers below: