The Doctor closes his eyes and when he reopens them, the steam vanishes, leaving them a clear pathway to the shed. He turns to her and grins.

"I've never been much for rules."

And, in protest, he hears a crumbling sound, followed by the sound of the TARDIS dematerializing in the distance. Things that would frighten him, make him run away.

He nods, and starts towards the shed. "There's more illusion here than reality right now."