The Master looks down at the Doctor's hand on his wrist—and, when the Doctor pulls away, he doesn't look back up. He holds still, hearing the drums quiet in the back of his head, waiting. His eyes go distant and inward-turned, as he follows his own thoughts.

He could challenge again.

Or he could choose to obey.

He looks up at the Doctor, and meets his eyes, unsmiling and serious. Without another word or gesture, he steps over to the bed and lies down, as per the Doctor's almost-orders.