We watch “The Power of Three” (Series 7, Episode 4) where the Doctor meets up with UNIT: The Next Generation and the Ponds are bored by alien cubes that do nothing…until they need to do something! Whilst the exploration of said cubes is occurring, Amy and Rory go about their lives, the Doctor pops in and out occasionally and life essentially continues unaltered. Until it doesn’t. When that happens, the Doctor and the Whoby crew jump into action and stop whatever nefarious deeds from occurring. Like you thought they wouldn’t?