Blackly comic gender-bending reworking on Robert Louis Stevenson’s oft-filmed classic; this was Hammer’s third variation on the tale after The Ugly Duckling and The Two Faces of Dr Jekyll.
It is camp, irredeemably silly and hugely entertaining, but the witty script written by Brian Clemens (longtime writer and producer of The Avengers TV series) never ventures into sexploitation and the excellent cast led by Ralph Bates and cult-queen Martine Beswick manage to keep straight faces.
Set in Victorian London, good Dr Jekyll (Bates), is experimenting on corpses supplied by infamous grave-robbers Burke and Hare to discover ways in which to prolong life.
He tests the formula on himself and metamorphoses into an evil temptress, Sister Hyde (Beswick).
His alter ego turns out to have a very nasty streak, killing East End prostitutes who, terrified of Jack the Ripper, believe they have nothing to fear from a woman.
Meanwhile, Jekyll falls in love with his attractive upstairs neighbour (Susan Brodrick), and Hyde is taken with her brother (Lewis Fiander), leading to much confusion and an unexplored struggle between sexual identities.
Roy Ward Baker