Surgeon Frederick Carver (Kenneth Williams) has his eyes on a wealthy female patient to donate him enough money to set up a private clinic. In the same hospital, Dr James Nookey (Jim Dale) is working in Casualty when his fantasy pin-up, Goldie Locks (Barbara Windsor) is wheeled in. After causing havoc, he is told off by Carver, who sends him to a clinic on a remote island. Here, however, Nookey makes an astonishing discovery - a slimming potion that works instantly! Sensing he has discovered a gold mine, he sets off to market it, much to the annoyance of Carver and others who will not let him succeed without a fight.