The writer for the opening episode of Sherlock‘s new season has been revealed.

The first of three new feature-length episodes began filming earlier this week, directed by Rachel Talalay (Doctor Who, The Flash).

Episode 1 is written by Sherlock co-creator Mark Gatiss, it’s been unveiled in an photo of the script posted officially on Twitter.

Gatiss has previouly written Season 1’s ‘The Great Game’, Season 2’s ‘The Hounds of Baskerville’ and Season 3’s ‘The Empty Hearse’. He also co-wrote mini-episode ‘Many Happy Returns’ with Steven Moffat and Season 3’s ‘The Sign of Three’ with Moffat and Steve Thompson.

> Here’s everything we know about Season 4 so far.

Mark Gatiss and Steven Moffat teased yesterday that the new season of Sherlock will be the climax of “the story we’ve been telling from the beginning.”

> Buy ‘The Abominable Bride’ special on DVD on Amazon.

> Buy the complete Season 1-3 boxset on Amazon.

Are you looking forward to Season 4? Let us know below…