>> Lock, deadbolt, and/or barricade the door. Look for another exit out of the room.

For now, you shift the heavy boxes in the corner of the room beside the door, over so that they block it. You have no idea how strong the creature might be, or if it can even open doors at all, but you’re sure as hell not taking any chances.

Shifting the boxes reveals a grate behind where they had stood, but you don’t see any other exit, unless perhaps there’s a door in the deep shadows by the edge of the lockers, but you were pretty certain when you were by the desk that it was only old office equipment.