‘Only Murders in the Building’ Adds Third ‘Doctor Who’ Star to Its Cast

Hulu’s Emmy-winning murder mystery comedy has never been shy about stacking its cast with recognizable faces, and Season 6 has already proven to be its most ambitious casting effort yet. With the show relocating from New York City to London for the very first time, ‘Only Murders in the Building‘ has spent the summer steadily unveiling one of the most star-studded ensembles in its history.

That London relocation opened the door for a wave of British and Irish talent, kicked off in June with the addition of David Tennant and Jodie Whittaker, two actors whose careers are inseparably tied to ‘Doctor Who.’ Tennant, known for playing both the Tenth and Fourteenth Doctor, and Whittaker, who made history as the franchise’s first female lead in the role of the Thirteenth Doctor, joined a growing recurring cast that already included Nicola Coughlan, Jim Broadbent, Richard Ayoade, and Kathryn Hunter.

Now the show is deepening its ‘Doctor Who’ connections even further. According to Deadline, Peter Capaldi has joined the Season 6 cast, marking the third actor with direct ties to the iconic British sci-fi franchise to join the ensemble this season. Capaldi previously played the Twelfth Doctor, a role he held before handing the TARDIS keys over to Whittaker in 2018.

Capaldi’s casting adds an intriguing layer of overlap to an already dense web of franchise history within the show’s guest roster. Whittaker took over the role directly from Capaldi’s Twelfth Doctor when she became the Thirteenth incarnation of the character, meaning two actors who quite literally passed the same fictional role between each other are now both part of the same murder mystery ensemble.

Even Jim Broadbent, already confirmed for the season, carries his own loose ‘Doctor Who’ connection, having voiced a version of the Eleventh Doctor in the spoof special ‘The Curse of Fatal Death.’ Between Tennant, Whittaker, Capaldi, and Broadbent, ‘Only Murders in the Building’ has effectively assembled its own miniature ‘Doctor Who’ reunion inside a completely unrelated show.

Character details for the new London-based cast members remain closely guarded, consistent with how the series has handled its previous celebrity guest reveals across earlier seasons. Given the show’s pattern of casting recognizable actors as suspects, victims, or red herrings within its central mystery, fans are likely to spend the months leading up to release speculating on exactly where Capaldi and his fellow ‘Doctor Who’ alumni fit into the story.

Season 6 will pick up directly from the shocking Season 5 finale, which solved the murder of the Arconia’s doorman Lester while introducing a new central mystery, the murder of podcast rival Cinda Canning, played by Tina Fey. Steve Martin, Martin Short, and Selena Gomez all return as Charles, Oliver, and Mabel, continuing their investigation well beyond the confines of their usual New York apartment building for the first time in the show’s run.

Alongside Capaldi and the previously announced British ensemble, the season’s recurring cast already includes major names like Martin Freeman, Sharon Horgan, Simone Ashley, and Geri Halliwell-Horner, rounding out one of the largest guest rosters the show has ever assembled. With production currently underway in London, Hulu has not yet announced an official premiere date for the new season.

Given how consistently ‘Only Murders in the Building’ has turned celebrity cameos into some of its most talked-about twists, Capaldi’s addition only raises the stakes for figuring out exactly who’s guilty this time around.

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