The blast was big enough to throw Theo out of his chair, as the very room shook and large pieces of the ceiling fell to the floor. His ears were ringing and his lungs felt as if they were filled with dust as he got up and stumbled through the door of his office. His secretary lay motionless across her desk, blood spreading on the surface. On top of her was a piece of the ceiling, she'd never had a chance.
He stumbled through the corridors, forgoing the lift and going to the stairs. People were trying to get out, but he pushed through them, leading the way only to turn when met with the chaos that was the Atrium.
Everywhere people were screaming, running, fighting each other to get to the floo first. In the midst of it, there was Death Eaters, shooting down people at random. Turning, Theo fought his way back. There was no way out through the Atrium, and he wasn't about to die of some random spell.
Going down took longer than going up, but he managed, not stopping on level nine but moving down to the courtroom on level ten. It was as deep into the ministry as you got, and if he wasn't safe in here he wasn't sure where he would be safe. He'd wait, see what happened, and if Voldemort took over he'd play his part well.