"Apollo 11's your secret weapon?" "No, no. It's not Apollo 11. That would be silly. It's Neil Armstrong's foot."
IN THIS ONE... The moon landing. Amy's unpregnancy. Nixon as companion. Marking your skin to remember the Silents. And a little girl who regenerates in the end.
REVIEW: Three months later and Amy's not showing. She's already been replaced. I think she may have been replaced as early as the near-end of The Impossible Astronaut when she clutches at her stomach in pain. Sorry to start with a theory/spoiler, but in many ways, that's the only sort of thing one can talk about in Day of the Moon. It's a collection of memes and puzzle pieces, some of which pay off by the end, others much later down the line. The plot itself is simply driving towards a solution announced in the teaser, an effort in collecting all the pieces necessary for the the Silent-routing solution. It's a clever use of the planet's most watched event, but seems fairly inevitable. We may not know what the plan is - and the teaser is certainly full of fake-outs - but the Doctor does. We're outside looking in, puzzling it out, and our cluelessness is mirrored in everyone who's forgotten the Silents. These kinds of touches abound as indicators of what's really going on. In the opener, all the companions are killed, which turns out to be a hoax... just like the Doctor's own death in the previous episode. A long time has passed since the last cliffhanger, just as periods of time are missing from the characters' lives due to Silent interference. Rory remembers his time as a centurion and doesn't. Amy is pregnant and isn't. Both have an artificial existence and a real one (we just don't know about Amy's yet). Rory eavesdrops on Amy, just like the Silents always do us. The joke about the "time head" turns out to be true.
But it's not all intellectual. There's something quite visceral about the Silents and much of the story plays out as a haunted house creepfest. The Silents are effectively invisible, but leave manifestations in the form of messages actually left by those who see them. The marks on the skin seem to appear out of nowhere, the orphanage man writes on the walls, and so on. When we do see them, they're cadaverous "grays" (no doubt that's how repressed memories of third encounters got their start), who sleep hanging from the ceiling like vampire bats. It's Gothic meets the Space Age, with strange hallucinations (the eye patch lady from Amy's other life), stormy nights and flickering lights. Great use of locations throughout.
Let's not forget the emotional character moments either. Amy finding pictures of herself with a baby, or whimpering in the dark for a savior to come. River realizing the Doctor's first kiss is her last, beginning the slippery slope to her natural end. Rory's thread is weaker, if only because it plays on his insecurities ONCE AGAIN. He anxiously listens to Amy's livestream, and believes she's talking to the Doctor and not him - sad face. It's got its moments, like his resolve to always be there for her, but it's essentially manufactured angst. It SOUNDS like she's talking to the Doctor because of Moffat's knowing word choice. Hopefully, this issue is put to rest by the end, with Amy frankly surprised anyone would think she fancied the Doctor (from her expression) and genuinely identifying him as her platonic "best friend". The two of them together are basically children having make-believe adventures, and respond to one another in that way. Sexuality no longer comes into it. It's not all dark, sad and spooky either. Canton remains a great ego-buster, genial Nixon absurdly comes out of a cupboard to fix things with NASA or the military, and if you like jokes about Rory dying, well, take a seat and get comfortable, it'll get told all season.
SECOND OPINIONS: My original review, The Impossible Astronaut / Day of the Moon: More Questions Than Answers! is obviously written WITHOUT hindsight, which I guess is no less legitimate an approach.
REWATCHABILITY: Medium-High - When first seen, it's a fine, atmospheric puzzle show. On repeat viewings, it loses some of its power from our knowing the answers.