Don't let him out. The Doctor figured that he could manage that easily enough if he really tried. How strong could the thing be, after all, when it was just a hollowed out corpse that had somehow been animated? By something a bit more impressive than clockwork, he hoped, as he whipped out his sonic screwdriver and flashed Amy a playful grin, "Back in a jiff," The Doctor said before pulling the supply closet door open and jumping inside, closing it with a swift BANG before its occupant could get much more than a glimpse of the outside world.
Though, the second that the Doctor found himself shut up inside the cupboard with an irate mummy and nothing more than his sonic screwdriver for illumination, he realized that he probably hadn't thought this out very well. The sudden thrashing that accompanied his presence just reinforced those thoughts, and it wasn't long before the Doctor was grappling for control in a closet battle royale.
"Oy, mate! Hold still. I just want to get a look at you," The Doctor managed to get out over the grunts and guttural moans from his uncooperative patient. Flailing to try and position the sonic screwdriver in vital areas despite the arms that were attempting to both bash him about the hand at strangle him, it wasn't until his sonic was sent flying out of his hand and into the closet wall, clattering uselessly onto the floor a second later, that his patience in the situation shattered. "Didn't your mummy ever teach you manners?" The Doctor huffed, bending to retrieve his sonic before it was trampled in the close confines and then hustling himself quickly out of the closet.
Casting a glance at Amy, he managed a gaze which he thought made him look far less ruffled than he actually was. "He's not very cooperative."