A man in his mid-thirties receives the news that his wife is unable to bear children. Devastated, he stops at a park bench to contemplate his future whereupon he notes the ease and fluidity of a seagull hovering above him. Stopping at a bookshop, he finds a book called ‘the wisdom of birds’ that draws a parallel between the lives of birds and humans. Reading the book beside the canal, the man encounters a woman and child and engages her in a conversation about parenthood. The encounter swiftly deteriorating as the woman expresses sympathy for his wife, drawing parallels between the collusive nature of birds that the man has just read about. Returning home, the man challenges his wife over dinner, linking her infertility to a desire to control him, likening himself to a little flea that has to ‘hop, hop’ to attention. Over the course of the next few days the man becomes increasingly obsessed with the book on birds, finding more and more parallels between their behavior and that of his wife, whom he now likens to a cuckoo, a bird that ‘steals the nests of other birds’. Growing ever more lost in his own mania, the man gradually begins to craft an enormous nest in his lounge, his delusion leading him to believe that ‘if he builds it, they will come.’ Finally, the wife attempts to confront her husband’s madness, desperately trying to break through his mania before he flies the nest forever.