The Master whirled away across the street, his whole hand beating out the rhythm on his trouser-leg now, helpless to stop it. Damn it, he had to get himself under control. He didn't want to give the Doctor even more reason to call him a child.
He breathed deeply, gradually calming himself, and finally turned back to the Doctor. "You can't help with the drumming without poking around in my head," he said, his voice low and almost steady. "And forgive me if I'm a little reluctant to allow that."
Not that he could be sure of stopping him if he tried, these days, but the Doctor didn't have to know that.