Lewis directed and co-wrote this entertaining version of Jeckyl and Hyde. The story still hadn't been explored at every level on the screen, and Lewis devised a good scenario from which to forge a comedy narrative about a nerd chemistry teacher who has no luck with women etc, suddenly being converted into a super cool, ultra confident alter ego who has no trouble with anything in life when he drinks a special potion he (as the nerd scientist) developed. It is slapstick mingled with sentiment, and delivered in Lewis' goofiest, daffiest style. It should be pretty appalling then, and does actually veer quite close to be being so on occasion, but the vibrance of Lewis' energetic performance, the brilliance of the contrast between his two polar alter egos, and the sultry Stella Stevens as his muse make this an enjoyable experience. It isn't subtle and of course ends in a moralising tone, but if you want a pretty basic sort of laugh at some great physical humour and funny visuals then this could fit the bill. People do get sniffy about such obviously physical film comedians as Jerry Lewis and Norman Wisdom but take a look at a couple of scenes here for visual mastery and simple fun. This has to be Lewis at his best, whether you like his idiotic style or not, and this movie can even be seen as an 'I don't need Dean Martin' injoke, as he does seem to take on an uncanny resemblance to the glass holding crooner in his alter ego as Buddy Love. Has some great goofy lines in it as well such as 'Carbon Dioxide (voice changes to that of Buddy Love) has always been a gas.' Memorable film, a great twist on the story and very entertaining. DVD has some good extras too.