"No mate, it's gone on too long. Sitting in your room and chatting, knowing exactly what he is doing!" Let's race is both shocked and his expression is filled with the kind of over-protective anger that Sherlock is too tired to comprehend.
"I quite agree with Gregory. There were assault mark all over Sherlock?" Mycroft asks, and he is thumbing his umbrella dangerously. If Sherlock were functioning better, he would be able to read the lines of frustration because the CCTV was taking time coming on.
"Yes, and that's not all. He slapped him, Mycroft, and then laughed at him and then hit him repeatedly. I can't, the bastard!" He is ranting.
Abruptly Mycroft's phone rings.