Ncuti Gatwa (Doctor Who, Barbie), Thandiwe Newton (Westworld, Crash), Maxine Peake (Silk, The Theory of Everything), and Danny Sapani (Halo, Penny Dreadful) have joined the cast of First Day on Earth, the upcoming HBO and BBC co-production, according to an official Warner Bros. Discovery press release. The announcement expands the ensemble attached to the high-profile limited series as production continues to take shape.

Per the release, First Day on Earth is created by and stars Michaela Coel (I May Destroy You, Chewing Gum), with the project positioned as a character-driven drama anchored by an international cast. While specific character details for the newly announced performers remain under wraps, Warner Bros. Discovery’s press release revealed character names for the new ensemble ahead of filming. The names are as follows: Newton will play Anya, Peake will play Helen, Sapani will play Ernest, and Gatwa will play Darren.

The series is being produced as a transatlantic collaboration between HBO and the BBC, continuing both networks’ longstanding model of prestige co-productions. The press release frames the project as a large-scale, scripted partnership supported by multiple production entities, aligning with both companies’ strategies for internationally developed limited-series programming.

mxdwn previously reported on the project’s initial announcement when HBO and The BBC first revealed plans to co-produce First Day on Earth. That earlier coverage focused on Michaela Coel’s creative leadership, detailing her role as writer, star, and executive producer while outlining the series’ foundational creative vision. The article also examined how the co-production structure reflected both networks’ investment in globally collaborative storytelling and auteur-driven television projects.

The newly announced casting by WBD press builds on that early development framework, reinforcing the production’s emphasis on experienced dramatic performers. Gatwa, Newton, Peake, and Sapani bring a range of film, television, and stage credits that align with theseries’s prestige positioning and ensemble-focused narrative structure.

While HBO and the BBC have not yet announced a premiere timeline, the steady rollout of casting updates signals continued momentum for the limited series. With its expanding international cast now taking shape, First Day on Earth continues to move forward into production as one of the network’s upcoming co-produced drama initiatives.