Landmarks No.49

A Good Man Goes To War.
The River Song mystery finally explained - and the news makes for a big impact on current companions Amy & Rory.
The introduction of what will become the Paternoster Gang - Madam Vastra, Strax and Jenny Flint.
Certain characters from earlier in the series (and the previous one) return.
Exposition about Kovarian and the Silence (though most will come in the following episode, which forms a sort of Part 2 to this).
One of the best pre-titles sequences ever.
Companions can't just be people who want to travel with the Doctor for a bit, as they were for many years. Nowadays they have to want to meet their dead dads whilst falling in love with the Doctor before being trapped in an alternative universe then nabbing their own personal version of him. Or exist in multiple versions across the Doctor's whole time-line. That sort of thing.
River Song turns out to be the child of Amy and Rory, conceived aboard the TARDIS and somehow imbued with Time Lord capabilities (like being able to regenerate). Poor Amy, wants to have sex with the Doctor on the eve of her wedding (even poorer Rory!). Gets married. Gets abducted. Only finds out she's pregnant just as she goes into labour. Has baby stolen and then meets her 15 minutes later as a mature woman whom she's already met and knows also has the hots for the Doctor.
Oh for someone who just wants to travel and see the Universe again...
The Paternoster Gang are certainly popular - especially comic Sontaran Strax. Mr Moffat continues his tendency to actively ignore his predecessor's era - so no Captain Jack or Mickey & Martha when he's looking for a team to rescue Amy. This still jars with me. (Actually, Ood Sigma was due to appear, but he got cut - RTD still gets a credit for creating the Ood in the end credits).
I still say the Gang should get a CBBC spin-off series. Had the Sarah Jane Adventures continued, one of the characters would have been gay (Luke was due to come out). Let's have Vastra and her wife instead.
The space-flying Spitfires from Series 5 appear, and Captain Avery and his son reappear from earlier this series.
As for that pre-titles sequence on the Cybership. You might think there are loads better, but this particular Rory fan still rates it highly.