Common Sense Note
Parents need to know that violence in this monster flick includes the mother of a little boy being killed, non-graphically, by fire-breathing dragons. Deaths are not very bloody -- usually characters enveloped in CGI flames, eaten in one gulp by dragons, or falling. There is occasional swearing, smoking, and drinking.
Sexual
Content
Birds-and-bees talk about how dragons breed (about as explicit and realistic as claiming the stork is involved).
Violence
Non-explicit scenes of people killed by being engulfed in flames, falling from great heights, or snatched up in dragon jaws. One human-against-human fistfight. Dragons also shot at and killed.
Language
"A-hole," "wanker," "bitch," "hell."
Social
Behavior
Quinn overcomes his personal terrors (a childhood trauma in which he saw his mum killed) to return to the dragon's lair in London and triumph. Sub-theme about how a modern society might resemble a medieval one if some disaster causes civilization's collapse.
Consumerism
Names of major news magazines. A Reign of Fire video game exists. The plotline cleverly insinuates references to The Lion King and Star Wars, as today's movie blockbusters turn into the fairy tales of a movie-less future world.
Drugs / Tobacco /
Alcohol
Cigarette and cigar smoking, macho and celebratory drinking of liquor.