Dawn is, in many parts, an uncomfortable book to read. Butler really does not want to give the reader any easy answers, but instead makes us grapple with some tough dilemmas. The prose is deceptively easy to read, because the real struggle is trying to work out who you're “barracking for”, or what you want to happen.
Dawn is set in the aftermath of an all-consuming war which has wiped out human life on Earth. Lilith, the protagonist, wakes up aboard a spaceship – not for the first time – on which she's been woken up and put to sleep, and woken up and put to sleep, over and over again and put through a range of weird experiences over these bouts of wakefulness. At last, her captors present themselves to her, and explain what's happening.
Her captors are aliens, a species known as the Oankali. They perpetuate their own species through genetic engineering, basically hybridising themselves with other species they encounter in the galaxy. Seeing that humanity was just about the wipe itself out anyway, they've rescued as many of the survivors as they could, and now plan to splice those humans' DNA with Oankali DNA and (eventually) set those humans free to repopulate the Earth. Through their tests, they've determined that Lilith has the ideal personality to learn all about the Oankali and their culture, teach other survivors about the mission, and ultimately lead a new human society on Earth.
There is a fundamental flaw in the Oankali's plans, of course, which is that Lilith and pretty much every other human in the book abhors the idea of having their DNA tampered with and producing not-fully-human offspring. Although the Oankali are kind and well-intentioned in many ways, they refuse point-blank to consider the humans' autonomy in this regard, no matter how many times Lilith tries to explain things to them.
But as I said before, Butler couldn't make things as binary as “Oankali evil meddlers, humans good freedom-seekers”. Many of the humans who appear in this book are actually not very nice – there are incidents of rape and murder – while most of the Oankali are very caring, if prone to patronising behaviour. Oankali society is communal and theoretically non-hierarchical; extended Oankali names convey how you're connected to the broader society. They're far more disgusted by violence than humans are, and eat exclusively vegetarian diets. They have the ability to heal humans' wounds through touch (and give them pleasurable sex-analogue experiences); it confounds them that most humans find this alarming and terrifying, when in their minds they're only trying to do good.
But the overarching point that Butler seems to be making is that even if Oankali society is “better” than humans', humans must be free to decide their own fate without outside interference – even if, as the Oankali point out, that decision was apparently to wipe out the entire species in nuclear war. That position seems a bit dubious, but on the other hand you can't deny that the forced impregnation, DNA tampering, etc. that the Oankali go ahead with is icky, too (and has a real-life parallel to chattel slavery, when slavers felt entitled to treat other people as livestock and “breed them” accordingly). Lilith tries to take a middle position, where she's on good terms with individual Oankali and helps them out wherever possible, while still planning to bail on them and vanish into the jungle as soon as they let her loose on Earth. Most of the other humans hate this strategy though for being, in their view, too soft.
This is a many-layered story; there is also commentary on gender, the difficulty of falling in love in an environment where you have little control over your life, and more. The dominant themes are shared in common with other Butler books that I've read, like Anyanwu's efforts to escape Doro's clutches in Wild Seed or Teray's conflict between being compromised but safe or free but endangered in Patternmaster. That said, the reason I've rated this book lower than those two is mainly that I was not so emotionally invested in it. Intellectually invested, sure, but the characterisation wasn't as gripping. Still, this might improve over the rest of the trilogy, and I'm still interested to see how things play out from here.