He was Ser Donnel Waynwood in Series Four of Game of Thrones and between 2014 and 2016 he was Chapman Carter in War Horse at The New London Theatre.
He was Richard in the BAFTA-winning and Oscar-nominated The Bigger Picture, a short animation film directed by Daisy Jacobs.
He has narrated over 300 documentaries including Pompeii: The Last Day, Lost Land of the Jaguar, Expedition Borneo, Operation Iceberg, Doctors in the Death Zone, The Somme – From Defeat to Victory for the BBC.
Other roles include Roy in Neville's Island at the Watermill Theatre, Gerald Croft on tour in Stephen Daldry's An Inspector Calls and Richard in The Years Between at the Royal in Northampton.
[citation needed] In 1996 Simpson appeared in the John Webster play The White Devil produced by the Royal Shakespeare Company at the Swan Theatre, Stratford-upon-Avon, England.