Bored during the summer holidays and escaping the heat, a group of kids (and their joey!) from Cook, on the Nullarbor Plain, discover a limestone cave with a huge underground lake. Meanwhile in town, a detective is called in from Port Augusta to investigate a stolen car and some sinister kangaroo shooters. When the kids discover their tucker and canoe have disappeared, they decide to do some investigating of their own. An Australian black and white short film written and directed by Tim Burstall (Alvin Purple).