Britain as the Setting
This film's setting in Great Britain is ironic, given the country's history. Britain has historically been the colonizer, extending its empire to the far reaches of the world and taking over different groups of people. In this film, Britain has isolated itself from the rest of the world, preventing foreigners from coming in rather than sending its own army out to attempt to colonize, as it had done in the past.
Baby Diego
"Baby Diego" is an ironic nickname for the world's youngest human, since, at the age of eighteen, he was technically already a legal adult when he died—far from a "baby," as he is portrayed. This nickname shows the extent to which infertility has affected the people of the world. They are longing for children again, and will latch on to the only remaining youth for as long as they can.
Kee's Pregnancy
Kee's pregnancy is ironic because of the message that the government of Britain has been trying to send about refugees. They have spent the last two decades painting refugees as harmful, uneducated terrorists, unworthy of human kindness. Meanwhile, it is a young refugee woman whose miraculous pregnancy holds the key to the future of humanity.
The Title "Children of Men"
The movie title itself is ironic, since there are no children remaining in the world depicted in the film. Due to the infertility crisis, the children of the world have all grown up without any new babies born to take their place; the youngest person on earth is over eighteen years old.
