The BBC has found its Guy Fawkes. RadioTimes.com can reveal that actor Tom Cullen – known to Downton Abbey fans as Lady Mary’s unsuccessful suitor Viscount Gillingham - has been cast as the 17th century conspirator in BBC1's new drama series Gunpowder.
He will star alongside Game of Thrones’ Kit Harington, who has already been confirmed in the role of Robert Catesby, the mastermind of the plot to blow up Parliament.
Sherlock’s Mark Gatiss has been cast as spymaster-in-chief Robert Cecil, with Lord of the Rings actress Liv Tyler playing Catesby’s cousin Anne Vaux who becomes suspicious of her relation's activities.
However we can also reveal other new castings. Broadchurch star Shaun Dooley plays Sir William Wade, Lieutenant of The Tower and Cecil’s right hand man, with some light relief possibly coming from comic actors David Bamber as the Earl of Northumberland and Kevin Eldon as Sir Joseph Hawksworth.
Also cast is Wolf Hall actor Edward Holcroft as Catesby’s friend and co-plotter Thomas Wintour, and Robert Emms as Father Gerard, a firebrand young priest.
Derek Riddell has been cast as King James I of England, with EastEnders actress Sian Webber playing Catholic sympathiser Lady Dorothy Dibdale. Spanish actor Pedro Casablanc plays the Constable of Castille, who was involved in the conspiracy.
The three-part drama will focus on Catesby, the 30-year-old Warwickshire gentleman who masterminded the failed assassination attempt on King James.
Recently Harrington revealed that he was descended from Catesby and that he had an interest in bringing his ancestor's story to the screen.
A contemporary portrait of Robert Catesby
A committed Catholic in Protestant England, the drama will portray his struggles to bring up his young son in an increasingly intolerant society, having recently lost both his wife and father.
He is angered by the suffering of his fellow Catholics, despite the pleas of Jesuit Father Garnet (played by Top of the Lake actor Peter Mullan) for peaceful protest.
The 17th century thriller has been written by Ronan Bennett and will be directed by J Blakeson. Filming is due to begin later this month for a likely broadcast in the autumn.