Kaitlin has fallen victim to her shadow, and as usual, it's up to Martin and Billy to save the day. They've found out that since the people who were safe slept in the light, that's the thing the shadow creatures are afraid of. With the help of the Legendex, they realize that the shadow creatures' leader, Barock the Faceless, wants to take over Earth, but needs all the humans in his realm before he can crossover—and when he does, the gateway will forever close. When Billy's gone too and Martin is the last being on Earth, the showdown begins.