In the supposedly borderless Europe of the 21st century, one frontier still holds firm—the Bidasoa River, separating Spain from France. At its heart lies Pheasant Island, a tiny sliver of land that alternates sovereignty between the two countries every six months. When the body of an undocumented immigrant is discovered on the very day the border shifts, Nassim, one of the survivors, becomes the target of a relentless manhunt by French authorities as he attempts to cross into Spain. Who is responsible?

This harrowing incident sets off a chain of events that will forever alter the lives of Laida and Sambou, an interracial couple caught in the crossfire of migration, identity, and state power.