Photographed this yesterday, beside a stream in a predominantly Beech woodland. (Couldn't get across the stream to get any closer for detail shots).
It looks like one of the Stock family.
I've discounted: -
Cuckoo Flower - leaves wrong shape.
Coralroot - no leaf node bulbils.
Pinnate Coralroot - leaves wrong shape.
Honesty - leaves wrong shape.
Dames Violet - stamens are yellow not violet.
The only thing I'm left with is Greater Cuckooflower -
Cardamine raphanifolia, which I think the plant actually is, but again the leaves don't seem to be just quite right.
Any help with ID confirmation/other appreciated.
Regards
Mike.