Also reprising their roles from the BBC TV drama, which ran for six series, are British actors Stephen Graham and Sophie Rundle.
Boiling Point star Graham played docker Hayden Stagg and Gentleman Jack actress Rundle portrayed Ada Thorne, the only female Shelby sibling in Steven Knight’s TV show.
Dune actress Rebecca Ferguson and Pulp Fiction star Tim Roth are also among those joining the cast, as the action shifts to follow the Shelby family into World War Two.
In 2023, Keoghan won a best supporting actor Bafta for The Banshees of Inisherin, and has also been nominated for roles in Saltburn and Calm With Horses.