For nearly 20 years, the Green River Killer haunted Washington State with a series of shocking murders. The two-part movie is told through the eyes of a young runaway, Helen Remus, whose fate, bad luck, and unwise choices led to her encounter with the notorious serial killer. Leading the hunt for the murderer is Sheriff David Reichert, who risks it all to find justice for the slain girls.

The Green River, the most significant tributary of the Colorado River, runs 730 miles and has been stopped up by dams, slaked off by irrigation, and dried up by cities. Former raft guide and environmental reporter Heather Hansman paddles the river from source to confluence to see what the experience might teach her about the present and future of water in the West.