The BBC have released a short synopsis for episode 3 of Series 9: "Under the Lake". The episode is written by Toby Whithouse ("The God Complex", "A Town Called Mercy") and will air on BBC 1 on Saturday 3 October 2015. The time is yet to be confirmed.
When an Underwater Base comes under attack, the Doctor and Clara must save the frightened crew and defeat an impossible threat. But what is behind these terrifying events? And can they really be haunted by ghosts?