‘The Bridges of Madison County’

Clint Eastwood (as director as well as co-star), Meryl Streep and Richard LaGravenese have pooled their resources and turned “The Bridges of Madison County” into a surprisingly moving feature. Few books have been shrugged off so casually, as Robert James Waller’s slender story of a passionate four-day affair between a careworn Iowa housewife (Streep) and a charismatic photographer (Eastwood). (HBO Saturday at 8 p.m.).