The Lannisters send Myrcella away from harm; Arya has a surprise visitor; Dany makes a vow; Robb and Catelyn receive crucial news; Jon gets a chance to prove himself.
A spaceship crashes into the Thames, causing the world to panic.
The Doctor, Rose and Harriet Jones are trapped inside Downing Street while outside, interplanetary war looms.
The team reels over the news about the mole; the Soviet plot continues; Wendy gives the team a much-needed break; Alan makes a tough decision when Sarah is in danger; leaked information threatens the investigation.