Even without the gunshot, bullets penetrating a skull had a very distinctive sound. One that Trowa knew all too well.
Automatically, he threw a nearby table over-- in the corner, he noted-- and fell into a crouch behind it, eyes still adjusting, gun held in a teacup grip. The shots had come from above, and toward the back/center of the room. They had the high ground, but other people had been in possession of that before and he'd still won.
Whoever it was, they were watching him. Well, that was fine. Trowa was a better shot than most, and he could remain behind cover. The person in the ceiling would be looking towards the sun.