Combat Medic Allyson Hanover must face the impossible, the loss of two lives that were in her hands - before a raging Colombian river ripped them away. When fellow Medic Reuben Fehlman joins a field test to develop new swiftwater rescue techniques, they both land in the rushing waters on Henderson's Ranch. Emily, Mark, Michael, and even Noreen can't crack it. To survive the swiftwater? The two of them must brave the current - together.