"It was never going to be a gun for you, Doctor. The man of peace who understands every kind of warfare, except, perhaps, the cruellest... Kiss, kiss."
IN THIS ONE... Amy and Rory's childhood friend Mels regenerates into psycho River Song, who almost kills the Doctor.
REVIEW: What fun! Let's Kill Hitler is a historical romp that fits the tone of The Romans, where the powerful and dangerous men of the past become the objects of farce and ridicule. Rory gets to punch Hitler, tells him to shut up, and stuffs him in a cupboard. Hitler is the butt of a joke. Another antagonist here is also a joke - the Tesselecta. This completely mad idea just about works because we're clearly in a comedy, but the concept is truly loopy. A man-sized shape-changing machine crewed by miniaturized humans who travel through time to inflict pain on criminals the moment before they die is not something you see every day (though you've already seen it... spoilers!). Even more absurd is the fact that these guys are complete rubbish! They realize they're at the wrong end of Hitler's career in the nick of time, and go after River Song at the wrong point too. Plus, their own security systems are likely to turn on them if there's the slightest malfunction aboard ship. The antibodies are rather polite, comforting killing machines, which is part of the humor, but one wonders why they're even needed. Do bugs get into the works often, or did the crew commandeer this thing by tricking the robots, but were never able to get rid of them? In any case, they don't manage to bring anyone to justice, and even lose control of their "mech" thanks to Amy's quick thinking.
The actually dangerous antagonist in Let's Kill Hitler is Melody Pond, and she too will be "disarmed" by the end. It's here, we're finally seeing River Song's first chronological meeting with the Doctor. This too is all played for laughs. A creature born of a time loop, Melody/River was named after herself. Making great use of little Amelia Pond, we flash back to what is only the latest update in the timeline where Amy and Rory are kids hanging out with troublemaker Mels, actually a regenerated Melody, and the future Mrs. Doctor. Not only does Mels grow up with her own parents, but she makes sure they get together in the first place (amusingly, Amy might have continued thinking Rory was gay if not for her) and, more darkly, positions herself where she can best assassinate the Doctor and complete her Silence programming. Love the transition between past and present, with the toy TARDIS turning into the real one, by the way. Who knows, if Amy and Rory's crop circle was inspired by the way River normally contacts the Doctor, it might also have inspired Mels/River to do the same kind of tricks, studying archaeology to help her do so.
The regeneration into Alex Kingston (not River quite yet) continues the fun and comes with the usual sexy innuendo. This carries over from Mels who thought he was "hot", and on the heels of a comforting marriage proposal when Mels was at death's door. Moffat pulls one of his old tricks from The Curse of Fatal Death, though without actual time travel, where we see move and countermove in the lethal dance between assassin and victim. Ultimately, it's love that does the Doctor in. Apparently, there's more than one brand of trick lipstick. After this, River becomes more of a distraction, blasting Nazis with regeneration energy (you can thank RTD for making that stuff destructive in The End of Time) and asking restaurant patrons to strip so she can get a new wardrobe. Meanwhile, the Doctor is dying. The business with the TARDIS' voice interface isn't particularly useful, though it's kind of fun to see he still feels guilty about Rose, Martha and Donna (Adric gets no respect), and what makes him come alive is probably a hallucination. The Amelia Pond interface was a skipping record, and it's doubtful "fish fingers and custard" would have been part of his vocabulary. It's all rather strange that he chooses to change into a tuxedo for his death, but as we'll discover when we cover Night and the Doctor, this was the type of thing he wore for his dates with River, so there must be an emotional connection there. He even whispers something in her ear, likely the thing Ten never told Rose. Melody is turned in those moments, and indeed, turns into River Song (which a weird waste of the whole mistranslation thing from the previous episode, or perhaps another game of what came first) and saves him with regen energy. There a problems with all this, of course. It was established in Forest of the Dead that one wouldn't regenerate from getting fried by the Library computer, so there's no need to take River's lives away. And if she gave all her regenerations to the Doctor, why is he out of them by Matt Smith's last story? (Indeed, the Doctor thinks he might regenerate from being poisoned, at one point. Perhaps this is when he finds out Ten wasted one.) It's possible this was an answer to the 12-regeneration limit that was discarded when a better story was thought up for Matt Smith's ending. It's not particularly troubling when Let's Kill Hitler is watched in isolation.
ADDITIONAL MATERIAL: The DVD includes a teaser/prologue that's essentially a voice mail message from Amy asking the Doctor when he'll have news of her missing baby. It's atmospheric, includes a couple of sweet jokes without undercutting her despondency, and ends on a great shot of the Doctor, not heroic but rather despondent himself.
SECOND OPINIONS: My original review, Let's Watch Doctor Who (oh, and Kill Hitler), talks about these points and many others.
REWATCHABILITY: High - Though there's a lot of nonsense here, it's couched in comedy and becomes part of the fun. And you don't want to miss River Song's secret origin anyway.