Hammer's Dracula and Frankenstein movies starring Christopher Lee and/or Peter Cushing are probably their best known, but dig deeper and you'll find some even more original and inventive movies from the studio. Like 'Dr. Jekyll and Sister Hyde', one of the very best. Ralph Bates had appeared in a couple of not very good Hammer movies prior to this, but he's perfectly cast as Dr. Jekyll and the choice of the stunning Martine Beswick as his alter ego makes this really something to see! Beswick had already been a Bond girl and co-starred with Raquel Welch in Hammer's unforgettable trash classic 'One Million Years B.C.' before this. She later appeared in cult favourites like Oliver Stone's 'Seizure' and 'The Happy Hooker Goes To Hollywood', but this to me is the definitive Beswick role. She is so sexy and evil in this movie, you'll never forget her once you see it. Gerald Sim plays Jekyll's horny colleague Professor Robertson, and Jekyll and Hyde's lives are complicated by their respective love interests (sister and brother) Susan (Susan Broderick) and Howard (Lewis Fiander). Broderick is really lovely. She seemed familiar but it wasn't until I looked her up that I realized where I had seen her before. David Hemmings buys something from her antique store towards the beginning of 'Blowup'. Fiander incidentally appeared with Gerard Sim in 'Dr.Phibes Rises Again' the year after this, but did very little subsequent horror work. As well as the great cast, the movie is helped enormously by a fresh script from Brian Clemens, and the solid direction from Roy Ward Baker, who had both previously worked on 'The Avengers'. It's funny, most fans immediately name Terence Fisher as Hammer's best director, but Baker directed three out of my Top Five Hammer movies (the others being 'The Vampire Lovers' and 'Quatermass And The Pit'), so I'd choose him instead. 'Dr. Jekyll and Sister Hyde' is wonderfully entertaining, and I give it my highest recommendation. If you've ever enjoyed a Hammer movie but haven't seen this one you're in for a real treat!