When does Gunpowder return?

The three-part drama premiered on BBC One in the United Kingdom on 21 October 2017 and on HBO in the U.S. on 18 December 2017. The series stars Kit Harington, Peter Mullan, Mark Gatiss, and Liv Tyler, and is directed by J Blakeson. It is based on the Gunpowder Plot in London in 1605.