The movie asks all kinds of big questions. Who created us? Who created the creator? What's the difference between creating and destroying? Some of the answers are rather cynical, but others illustrate the general hope, empathy, sacrifice, and goodwill of human beings.
Gory monster violence, with blood and dead humans. In the most harrowing sequence, a woman finds that she has an alien fetus inside her, and she climbs into a medical chamber for emergency surgery. The bloody "baby" alien is removed from her via a very bloody C-section, and she's stitched back up again. In another sequence, characters are brutally attacked by an alien that eventually crawls inside one's body. Otherwise, an alien head explodes, an infected human is set on fire (alien bodies are also burned), a creature breaks a man's arm, and there's general fighting and chaos, including guns/shooting, and flamethrowers. Also, a little girl talks about death with her father. Aliens' bodies mutate and dissolve in a somewhat graphic fashion when they drink a particular substance.
No nudity, but a man and a woman are shown beginning to have sex in their quarters. They kiss and start to remove their clothing. Later, a man and a woman agree to have sex, but it's not shown. A female character is shown to be pregnant with an alien and is seen running around in just underwear.
"F--k" is used once, as well as several uses of "s--t." Other words include "bastard," "piss," "hell," "damn," "son of a bitch," "laid," "bugger," and "goddamn," plus "oh my God" and "Jesus Christ."
Drinking, Drugs & Smoking
One character gets very drunk as a response to bad news. Many of the characters are shown drinking hard liquor (vodka, whisky, etc.) socially at some point. One character smokes a cigar; in another scene, a character smokes an unidentified substance that makes him loopy/happy. Another takes necessary injections of painkillers.