The Doctor had to secretly admit to enjoying watching the Master try to reassert his dominance and power to him in moments like this, but refrained from making a comment when that horrid noise occurred.

"I have no idea." His head nearly snapped off as he quickly turned in the direction it occurred, brows furrowed and mouth slightly ajar. "It sounded almost mechanical in nature..." It was only a guess as he took a step back from the Master and began slowly walking in that direction until there was a fork in the hallway.

"Left or right?" He found it suspicious that no one had come to greet them yet. "Have you noticed any cameras?" He hadn't, but wondered how advanced the technology was here.