With Rachel close to a breakthrough on her vaccine, she, Chandler and XO Slattery lead a small team into the jungles of Nicaragua on a mission to find monkeys for her vaccine trials. While there, they find much more than they bargained for when they run across a former drug kingpin who will stop at nothing to maintain his stranglehold on his oppressed society. Chandler and his men find themselves in a huge moral dilemma over whether to eliminate this menace or take what they need and continue on with their mission.

With Chandler and Tex caught in a dangerous situation, Slattery has to step into the role as commanding officer. Torn between a mission with the fate of the world at stake and a Captain (and friend) in danger, Slattery has to find a way to get his people back without losing the most important asset: the vaccine prototype.