"Well - then. Looks like something to get to the bottom too." Especially, if it is powerful to teleport Ten here without his Blue Box. "What are the functionality of those things?"

The Doctor smiles back, "You were brilliant. Ah! But the future's here. At least till we both find a way back and I catch up with you... So, funny never thought I'd tell you that." As The Doctor squints about that notion.

"Did the Tardis arrive with you then?"

The Doctor goes unusually quiet, "Why did you lie to that Sirius person?" There is an underlying answer, with him not answering the question directly that the answer to her question is, no.