The Host (2006)

A family trying to retrieve a child has to work around official responses that create problems of their own. Bong Joon-ho moves from riverbank spectacle to messy domestic loyalty, letting humour and panic occupy the same scene. The monster has memorable physical presence, but the Park family's imperfect teamwork gives the pursuit its urgency. Choose it for a creature feature in which institutions and ordinary people are under as much scrutiny as the thing in the water.