It is a very tender romantic drama with such beautiful performances, sets, costumes, music and scenes that it has a resonance which places it almost in a league of its own among mini series.
Some others have commented on the difficulties of living as a lesbian in Britain in the 1890s. Nothing especially difficult about that; it was only male homosexuality that was against the law as poor Oscar Wilde experienced to his great cost and as a great loss to the literary world. Anyway, I digress.
In my view, this is essential television. It is perhaps one of the greatest tragic romantic dramas since Romeo and Juliet, although not in the conventional sense.
10 out of 10 from me.