He pictured the Mariah Building in his head again. Access doors from the rooftop were located at the north and south ends of the building, leading down to the stairwells that corresponded at either end of the structure. The north end was furthest from their present position. Evidently the arriving bogey team didn’t have their exact location. It gave them a precious few seconds more. "Set off one of the audible alarms on the eleventh floor and make sure the security pads in that stairwell show it."