That is a nice white double John. To bad it has not set seed. Looks like a worth while hellebore.I would watch this flower very close.

Have you tried pollen from a different hellebore? Or the pollen of this double on a different hellebore. I do not see any ripen pollen in your picture, though the anthers do not look fully developed. The stigma does not look right, it may just be the picture, but the sexual parts all look odd.

I have a low cream H.x hybridus that produces no pollen but will set seed if you hand pollinate with another's pollen.

Bruce