Abstract: The present invention discloses a collapsible rigid shelter for mounting on a truck bed. The shelter includes a floor with a pair of floor extensions, a roof shell, a collapsible roof support and a plurality of rigid wall panels. In the transport configuration, the rigid wall panels overlap the floor. The shelter may be transformed to the deployed configuration by using to collapsible roof support to elevate the roof shell, sliding the floor extensions laterally away from each other, and moving the wall panels to extend between from either the floor or one of the floor extensions to the roof shell, and thereby collectively form an enclosure when the shelter is in the deployed configuration.