The BBC has published the official synopsis for the eleventh episode of Doctor Who‘s new season, titled ‘Dark Water’.

Written by Steven Moffat, the episode airs on Saturday 1 November on BBC One and is described by Moffat as “a proper scary one”.

The synopsis reads: “In the mysterious world of the Nethersphere, plans have been drawn up. Missy is about to come face to face with the Doctor, and an impossible choice is looming. ‘Death is not an end’ promises the sinister organisation known only as 3W – but, as the Doctor and Clara discover, you might wish it was.”

The finale is the first two-part story since ‘The Rebel Flesh’ and ‘The Almost People’ in 2011.

Season 8 continues this weekend on BBC One with ‘Flatline’.

> Here’s everything we know so far about Season 8.

Are you looking forward to ‘Dark Water’? Let us know below…