The series will air next year, with filming taking place in Liverpool. Irish actor Jack Gleeson has joined the cast of a new BBC show Hercule. The six-part series will be based on the beloved Agatha Christie detective, Hercule Poirot. AdvertisementFilming is expected to begin soon, with the shoot taking place in Liverpool. AdvertisementThe series is set to air on BBC and BritBox in 2027, produced by Mammoth Screen, part of ITV Studios, and Agatha Christie Ltd.