Abstract: A camper shell system for a pickup truck generally includes universal mounting plates and a structural support for a camper shell that comprises front, first, and second walls that extend downward from a top. The shell and mounting plates extend wider than the bed rails to cover a space above and to the sides of the truck bed. The structural support is sized to nest within and reinforce the camper shell and, preferably, to transfer forces acting on the camper shell to the bed of the truck. In one configuration, when the tailgate is down, the structural support is enclosed and operable to extend over the tailgate to enlarge the space covered by the camper shell system and to help bear the top of the camper shell.