Yes, he's right - it's a herbaceous clematis. Not sure which one, as mine is a different colour.

Thank you very much. It seems an awful lot of foliage for such tiny flowers.
My geraniums are growing at last, probably in flower next year!

Mad - such is the way with species Clematis species! I think this is C. heracleifolia incidentally.

i have C. heraclefolia Alan Bloom and it looks very like this. It is a lovely plant.

When I was about fourteen (33 years ago now) I was at a National Trust house with my parents (can't remember where now) and there was a bowl of C. heraclifolia (not the unscented Alan Bloom form) in one of the rooms. There were two elderly ladies asking someone what the lovely flowers were in the bowl. I overheard them and told my mum and dad that I knew what they were. They pushed me forward and said he knows. I said that it was a sub-shrubby/herbaceous Clematis called Clematis heraclifolia and that the flowers not only looked a little like Hyacinths but also were scented very like them too. They were very impressed with this information coming from one (to them) so young.

I like your story Fractal, clever little thing you were! Maybe you still are!
Thank you everyone else for responding. I'm really quite surprised that it is so well regarded as it looks so short of flowers and with lots of leaf. I didn't get the fragrance either because I wasn't close enough probably.

He's still in short trousers, aren't you, Fractal! LOL.

My herbaceous Clem. spreads all over the place - I don't mean rooting, it's just so very vigorous!

I'm in shorts at this very moment LOL

See? I'm psychic! LOL.