What’s causing the mutations? Is it contagious? Can the creatures be trusted, or are they a threat to others? A scar on Émile’s cheek, acquired during the early days of his mother’s infection, offers a hint of the risk. Through it all, 16-year-old Émile (Paul Kircher) and his father, François (Romain Duris), are just trying to stay calm, which isn’t easy when something akin to a zombie apocalypse has left the entire country jittery and suspicious. The mutations are slow and somewhat unpredictable: One person might sprout feathers, observing over weeks as their arms develop into wings, while another grows scales and winds up slithering like a snake. In “ The Animal Kingdom,” a mysterious malady is sweeping France, unlocking something at a genetic level that causes people to transform into hybrid creatures. While the world was grappling with the COVID-19 pandemic, French director Thomas Cailley was imagining another kind of coronavirus, one he’d cooked up before the crisis, but which suddenly took on new real-world relevance.