After discovering that Earth Force is waging a covert alien war, Jasper and his friends return to space and continue their training. This time, Earth Force brings them to the remote planet of Gulaga, where the cadets compete in the Tundra Trials, a grueling pod race across the planet's frigid landscape, but when their pod leader asks Jasper and Mira to secretly test a dangerous new technology that will take their Bounder abilities to the next level, the kids begin to suspect that there are rifts within Earth Force. The worst part? Jasper must keep the truth from everyone--even his own pod mates. When Earth Force prepares for an attack against the aliens, the kids are tasked with a treacherous mission.