Apple TV+’s Foundation is set to return to Prague in early 2026, with season four scheduled to begin filming on Jan. 5, according to new details from the Czech casting agency Extrafilms. The project will mark one of the country’s most extensive international productions of the coming year and, for the first time, the next season will be produced entirely within the Czech Republic.
Foundation has filmed significant portions of seasons two and three in Prague, but this marks the first official confirmation that the next season will again use Czech locations and studio facilities. The extended production window—spanning more than 120 planned shooting days—positions Foundation as one of the largest ongoing international projects currently slated for the Czech industry.
The casting update signals early preparations already underway. Fittings for extras are expected to begin in mid-December, and the production’s early-January start indicates a tight turnaround as crews return to the large-scale, effects-heavy universe the series demands.
Foundation returns to Prague
According to Extrafilms, season four of Foundation will be produced exclusively in the Czech Republic, a shift from earlier seasons that split locations between Prague and other international sites, including neighboring Poland. While Apple TV+ has not issued a formal announcement, the details released match expectations from industry insiders who anticipated the show’s return to Prague following September’s renewal.
The Jan. 5 start date places Foundation among the first major international productions to begin shooting in Prague in 2026. With more than 120 filming days planned, the commitment places the scale of season four on par with, or potentially larger than, previous installments.
Seasons two and three were based primarily at Prague Studios and used locations throughout Czechia to depict the series’ expansive planetary settings, combining practical builds with large-format visual effects work.
The new season follows a third-season finale that expanded the scope of the narrative, closing with The Darkness. That episode concluded major arcs involving Gaal Dornick, the Second Foundation, and the rising threat of the Mule, while signaling an uncertain future for the ruling Cleonic Dynasty.
Returning cast members for season four are expected to include Lou Llobell, Terrance Mann, Cassian Bilton, Synnøve Karlsen, Cody Fern, Tómas Lemarquis, Troy Kotsur, Brandon P. Bell, and Rowena King, though Apple has not yet confirmed the season four ensemble. Series stars Lee Pace, Jared Harris, and Laura Birn may or may not return for the fourth season following events in season three. New faces are also likely to be joining the cast.
Foundation remains one of Apple TV+’s most ambitious original productions, based on Isaac Asimov’s foundational sci-fi works. Apple renewed the series for season four days before the season three finale, citing its global viewership and critical reception. The third season retains Certified Fresh status on Rotten Tomatoes, a metric Apple highlighted when confirming the renewal.
Local industry impact
Extrafilms’ announcement also outlines an accelerated timeline for background casting, noting that its team is “working full speed” to prepare for January’s first shooting days. Costume fittings for extras begin Dec. 10, with registration sessions scheduled across three dates in early December. Prague locals interested in becoming an extra for the series can register in person; details can be found at the agency’s Facebook page.
For Prague’s film industry, Foundation‘s return represents another major international engagement during a period of steady activity. The project previously employed thousands of Czech crew members and contributed to ongoing demand for local studios, VFX houses, and support services. Its technical requirements—ranging from large-scale set construction to extensive costuming—have made it a reference point for the city’s ability to host high-end sci-fi productions.
The 2026 shoot follows a busy end to 2025 for Prague, which has recently hosted productions including The Age of Innocence and the third season of The Empress for Netflix, along with Zach Cregger‘s Resident Evil. The return of Foundation, with its long schedule and substantial infrastructure needs, is expected to be a significant contributor to local production volume in the first half of 2026.
While Apple has not yet released narrative details or confirmed broadcast timelines, the January start positions season four to continue Foundation‘s tradition of multi-year, large-scale production cycles. With Prague production extending into mid-2026, fans looking forward to season four will likely have to wait until 2027 for it to hit Apple TV+.
