A Town for Hire - S4.E3

St. John is following Jo in a bi-plane as she tries out a new navigation device in a helicopter over an area of wilderness, when her helicopter is suddenly struck from the ground by a laser-beam that sends her chopper crashing down. St. John's plane is also hit, but he manages to land in the nearby town of Santa Mira before he looses consciousness. Waking up the next day in the local hospital, he is infuriated that nobody seems to believe his story and is out looking for Jo. But when he arrives at the crash-site, there is no sign of the crash ever happened, and as St. John tries to find out what is going on, he finds that the small boom town is held in some kind of grip of fear...