Perhaps Doctor Who‘s most secretive episode of series 7 has finally begun to unravel its secrets in the official synopsis for “The Power of Three.”

Originally titled “Cubed,” episode four has been noticeably absent from all trailers and promotional material for series 7A so far. We knew it would guest star Steven Berkoff and see the return of Mark Williams as Rory’s father Brian (whom we will first meet in “Dinosaurs on a Spaceship”), but apart from that it appeared to just be a whole lot of black cubes. Finally, the BBC has put us out of our misery by revealing the official synopsis and first still from the Ponds’ penultimate adventure with the Doctor.

Doctor Who 7×04 – “The Power of Three”

“The Doctor and the Ponds puzzle an unlikely invasion of Earth, as millions of sinister black cubes arrive overnight, almost like presents falling from the sky.

“But what are they, what’s inside them and most importantly, who sent them? With the international community at a loss, it’s left to the Doctor to unearth who is behind the mystery.”

 

“The Power of Three” is written by Chris Chibnall and guest stars Mark Williams, Steven Berkoff and Jemma Redgrave (pictured above) alongside Matt Smith, Karen Gillan and Arthur Darvill. The episode will air in the United Kingdom, United States and Canada on Saturday Sept. 22, with no exact broadcast time officially confirmed.

Are you looking forward to seeing “The Power of Three”?