A screenwriter has spoken of his honour after the Doctor Who episode he penned was shown on air.

The episode, aired on Saturday, was written by Jamie Mathieson, 44, from Brighton, with the next due to be shown this weekend.

For the episode already shown, the former stand-up comedian took control of the Tardis to send the time-travelling Doctor and his companion Clara on an adventure on a space version of the Orient Express.

In his blog, Mr Mathieson, who has written two scripts for the popular sci-fi series, spoke of the achievement.

He said: “An honour. And a joy. And a huge pressure. And very, very cool. And a chance to shine in front of the biggest audience I have ever had.”

Darker side His episodes are entitled “Mummy On The Orient Express” and “Flatline”, with both episodes being flagged as potential game-changers, revealing a darker side of the Doctor.

The BBC’s official synopsis described “Mummy On The Orient Express” as set on the most beautiful train in history, speeding among the stars of the future when a deadly creature cuts the passengers’ enjoyment short.

The episode featured the famous time traveller racing against the clock at “his deadliest and most ruthless”.

Also on his blog, Mr Mathieson revealed that he found Doctor Who terrifying when he was a child.

He said: “I vividly remember literally hiding behind the sofa when the Daleks came on screen and still being able to see them in my head.”

Mr Mathieson also wrote four episodes for BBC drama Being Human between 2010 and 2013, as well as for science fiction comedy Frequently Asked Questions About Time Travel. His next Doctor Who episode is scheduled to air on Saturday at 8.30pm on BBC One.