[she smiles rather ruefully] North? You've got no idea. [out of everyone she met while she thought she was the Doctor, he certainly took it the worst. it still hurts to think about; she's never seen him so cold--certainly not toward her. but she quickly brushes past the topic] But like I said, it's been a while since all that 'appened.

[curious, she adds:] do you know 'im, then?

[it's perhaps a bit remiss for a detective to assume from the Doctor's words that he knows what he's talking about and didn't only just see the ring, but she probably has too much expectation of the Doctor knowing about everything already]