Denmark is five and a half million people, two directors who have won the Palme d'Or, and a film school that admits about six students a year. Carl Th. Dreyer worked in near-isolation for most of the century and made his films a decade apart, running a Copenhagen cinema in between to pay for them. Then in 1995 four Danes signed a set of rules banning tripods, scores and the director's credit, and got more attention than any Nordic cinema ever had — which is the tradition the country has been productively arguing with since.