Tony's eyes narrowed as he watched the gears turn in Donnie's head, just long enough that he started to doubt that the kid was going to reach the same conclusion and had just taken a breath to propose some alternatives and wave away the dumb idea when Donnie bolted. Tony remained where he was, mouth snapping shut to purse his lips as he bent over slowly like he could see Donnie's wake through the door as his footsteps echoed down the hall. A glance assured him that the mystery part was gone, and no new ones had shown up in its place. With a sigh, he considered the mess of the rest of the room, and how many boxes he would need to start packing.