Squadron Leader Marcus Yorke tells Worrals that a dead native has been found off the coast of Australia with a message written in holes through a metal tin "Help. Nine British girls .... alive .... island .... south-east Singapore .... Reward this man". Worrals asks for and is granted permission to try to find the lost girls. They have some information to start with. It is known that nine girls set off from Singapore in a bid to escape the Japanese invasion. Flying out to Darwin, Australia and taking advice from a local fisherman, Billy Maguire, our heroines fly on to make a base on Ingles Island. From here they plan to systematically fly over every island in an attempt to find the missing girls.