Peter Capaldi’s co-stars in The Musketeers have said that they were initially shocked that he was cast as Doctor Who but added that he’s perfect for the role.
Capaldi plays the villainous Cardinal Richelieu in the series although his new role as the Doctor will mean that he cannot return for a potential second series.
Maimie McCoy, who plays Milady de Winter, said: "He is perfect for it.
"He's also massively into it - I think he has been since he was very young which is great for the show."
Tom Burke who plays Athos in the TV show said: "It hadn't occurred to me and when he was cast, it just seemed the most brilliant decision.
"I thought, 'Of course!' so I'm very excited."
Actress Alexandra Dowling, who plays Queen Anne added that when she heard about Capaldi’s casting she felt "a mixture of elated and sad".
"It was so exciting and then we were like... 'Oh no!' but it was just such a privilege to work with him".
Doctor Who will return to BBC One later this year.