It's a good bet there are no directors who float between feature and documentary filmmaking as smoothly as Werner Herzog. The White Diamond (2005) is a companion piece of sorts to his well-received Grizzly Man. Both are about eccentric dreamers who travel to harsh landscapes following their dream with tragic consequences. In other words, perfect "Herzogian" fodder. Two important differences: White Diamond is filmed in the standard way (not piecing together another's videotape) and the tragedy occurred years before cameras rolled. Dr. Graham Dorrington is a man driven to fly. The Cambridge scientist creates new types of airships to explore the canopy of tropical rain forests. Herzog and his crew follow Dorrington to Guyana to see if this new-age dirigible can bring us closer to this fragile and important ecosystem.