Somewhere in Australia, a boy called Bob has fallen and is hurt. He thinks his leg is broken, but he manages to crawl to his bag and pulls out a radio. He calls International Rescue, and John Tracy picks up his call. John tries to talk to him but something seems to be wrong with the boy's radio. John gets in touch with Tracy Island and says that the boy could only transmit messages. But he stayed on the airways long enough for him to get a fix on where he was to within a mile. Jeff tells Scott to move out and Thunderbird 1 blasts off minutes later.