Identify this tv/show movie: Period drama with talking white mice?

I only spotted a bit of this on the television in the eye doctor’s waiting room a few weeks ago, but my curiosity has grown and google-fu is failing me.

It was live action, and seemed to be something rather like an English period drama. Couldn’t really pin down the outfits, but they seemed somewhat in line with the movie of “The Importance of Being Earnest.” Wandering around a grand old manor house and tea out on the lawn, that kind of thing.

And every so often, a young woman with blond-ish hair would sneak off to an isolated corner of the manor and have secret conversations with some white mice. (Possibly other talking critters, I’m not sure.)

Can anybody help me track this down?

My first thought was Stuart Little or the sequel but I think those were contemporary settings. I would try and remember the exact date and time you were at the office and then scan through tv guide listings to see if you can figure it out.

My first thought is the Hitch Hiker’s Guide To The Galaxy.

This.

The young woman with blondish hair makes me think The Witches rather than HGttG.

I was thinking The Witches(1990) also.