To save his job, David agrees to a shady plan: smuggling a mysterious package back from South America. He finds himself on a cruise with his ex, Tess, his son, Leo, and his colleague Stéphane, who is as simple-minded as he is clumsy. David decides to use Stéphane as an unwitting mule to carry the package for him. But everything goes off the rails when Stéphane accidentally opens it: an adorable baby Marsupilami pops out, and the trip spirals into total chaos!