Doctor Who confirms BBC One time slot for The Legend of Ruby Sunday

According to the official synopsis for the episode, it will see the Doctor and UNIT investigating Ruby's past. However, as the Time Window reveals horrifying secrets from Christmas Eve, the mysterious Triad Technology unleashes the greatest evil of all.

The cast list for the episode has also been unveiled, with the likes of Jemma Redgrave's Kate Lethbridge-Stewart, Bonnie Langford's Mel Bush and Yasmin Finney's Rose Noble all making a return, alongside new stars such as Lenny Rush as Morris Gibbons, Genesis Lynea as Harriet.

Susan Twist will also be back in what seems to be a major new role, playing Susan Triad – a character some have theorised to be related to the TARDIS, given the anagram created by her first initial and surname, S TRIAD.

Showrunner Russell T Davies has previously called Empire of Death – the season finale which will air a week after The Legend of Ruby Sunday – "literally, the biggest finale ever" and stressed that fans should try and stay up till midnight between Friday and Saturday to watch it when it becomes available on BBC iPlayer.

He told RadioTimes.com: "We are dropping these episodes at midnight, and if ever you’re going to stay up until midnight with a bottle of cider or a box of chocolates and sit there and watch Doctor Who, I would recommend it for that one – because you will be screaming.

"Try to stay unspoilt, because it’s so hard to be unspoilt with things. Try, try, try, and you will have a whale of a time with that one."

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Doctor Who continues on Saturday 8th June on BBC iPlayer and BBC One. Previous seasons are available to stream on BBC iPlayer with episodes of the classic series also available on BritBox – you can sign up for a 7-day free trial here.

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