This title is part of Bug Club, the first whole-school reading programme that joins books with an online reading world to teach today's children to read. In this Turquoise-B level Ben 10 book: Evil alien Vilgax has sent three aliens to try to recover the Omnitrix from Ben. Ben and Gwen are playing in an old silver mine when the aliens arrive. As Ghostfreak, Ben traps the first one in the mine. He is fighting the second one when the third alien, Hoverboard, arrives and turns out to be a friend. Hoverboard and Ben, as Grey Matter, defeat the two aliens.