Thanks to Spindae2 for the heads up.
Kemp will play Lord Darnley, a character based on the real-life English nobleman who would become the second husband of Mary Queen of Scots, played on the show by Adelaide Kane. Breezily confident, charming and warm, he was born with a blood claim of his own to the English throne and a wildly ambitious mother whose love hinges entirely on his ability to secure a crown.