Hugh Dancy, Laura Haddock, Nathalie Baye and Dominic West will join the principle cast.
The screenplay is by Downton Abbey creator and Oscar winner Julian Fellowes and BAFTA and Emmy nominated Simon Curtis is directing.
Making a comeback: Universal Pictures International will release internationally on the same date
Sequel: The film wraps production in August and the original cast will returned with some new additions (Pictured Kate Phillips, Simon Jones, Geraldine James Downton Abbey - 2019)
Emmy and BAFTA Award-winning Gareth Neame and Emmy Award-winning Liz Trubridge producing with Fellowes.
Although some scenes are filmed in studios and at different locations, the cast and crew spend much of their time at Highclere Castle - which is the home of the 8th Earl and Countess of Carnavaron, whose family have lived there since 1679.