"No, she's completely grounded by the force field - can't even take off - unless I set the parameters of the universe as the boundaries of this island. And then I obviously can't go further."

By the look on the Doctor's face, it appeared Sasha had hit upon one of the Doctor's current frustrations.

"It's just so... linear! Everything happens in the right order." [Dispairingly.] "I'm never going to get used to it."

He flicks a couple lever in frustration, but then looks up with a smile.

"And time does pass really slowly when you're not having adventures, but there are enough people to meet that I usually have someone to talk to."