An assembly is provided for opening a heavy weight door, such as on a military vehicle, by an occupant in the vehicle. The assembly includes a latch module with a catch and rotor adapted to engage and disengage the striker on the door frame, a blast lock module including a pawl adapted to engage and disengage the door frame, and a release handle module with a single interior handle for controlling the engagement and disengagement of the latch and blast lock modules. The three modules are pre-assembled on a carrier plate so as to form a rigid, unitary assembly for mounting on the inside of the door. When a person chooses to exit the vehicle, the handle is actuated so as to retract the blast lock and then release the latch. When the door is closed, a person inside the vehicle can actuate the handle so as to engage the blast lock for safety.