An exciting mystery for the whole family! When Oliver discovers mysterious holes in the ground and his bike has broken, he wants to find out who is behind it. Together with their detective friend Tiril, they try to find the culprit, who turns out to be someone who calls himself the Darkman. Will they be able to figure out who the Dark Man is? Double Deckers is also a popular book series by Jørn Lier Horst.