The Carls just appeared. Coming home from work at three a.m., twenty-three-year-old April May stumbles across a giant sculpture. Delighted by its appearance and craftsmanship – like a ten-foot-tall Transformer wearing a suit of samurai armour – April and her friend Andy make a video with it, which Andy uploads to YouTube. The next day April wakes up to a viral video and a new life. News quickly spreads that there are Carls in dozens of cities around the world – everywhere from Beijing to Buenos Aires – and April, as their first documentarian, finds herself at the centre of an intense international media spotlight. Now April has to deal with the pressure on her relationships, her identity and her safety that this new position brings, all while being on the front lines of the quest to find out not just what the Carls are, but what they want from us.