4. A Good Man Goes To War (2011)
Meanwhile, A Good Man Goes To War was by far a polar opposite to The Power Of Three, instead a blazing science-fiction adventure set out on the asteroid of Demon's Run. Pushed to the brink by the discovery of Amy being cloned into a flesh Ganger to distract him from her impending childbirth, Rory from the little town of Leadworth managed to stare down an entire Cyber armada in pursuit of his partner, with the help of the Doctor of course. That we see Amy's faith in the Lone Centurion explicitly spoken in her opening voiceover just goes to show the strength of the relationship that the Ponds have with one another. Many writers would have been content just to have a rescue story as a standalone episode, but Steven Moffat is no ordinary writer: instead, he continued to hit the Ponds with everything he had, sending sword-wielding Headless Monks and the agents of the Silence to grab the baby. It eventually transpired that Madame Kovarian had already escaped with young Melody Pond- was this the end of our favourite companions' relationship with the Doctor? Nope, because the mid-season cliffhanger turned out to be that the Doctor's soon-to-be-bride River Song was in fact Melody all grown up. Karen acted her heart out in the final scenes of this discovery, with Arthur magnificently holding her back as Amy threatened to pull the trigger on River if she did not explain. Scenes of raw emotion such as those will serve as a fitting memoir for these two brilliant characters.