On the subject of movie adaptations of Stevenson's Dr Jekyll and Mr Hyde, Hammer actually attempted this subject twice. Their first attempt was The Two Faces of Dr Jekyll in 1960, directed by Terence Fisher (also released under the title Jekyll’s Inferno). Not as unconventional as Dr Jekyll and Sister Hyde but still an excellent and very interesting version.
I still think the best-ever straightforward adaptation was the 1920 silent Dr Jekyll and Mr Hyde with John Barrymore. I've never been a huge fan of the much-praised 1931 Hollywood version and the 1941 version is simply awful in my opinion.
If you want a truly bizarre version there's always Walerian Borowczyk’s 1981 Dr Jekyll and his Women. It's worth seeing just for Udo Kier, but then anything is worth seeing for Udo Kier.