Although Tarzan warns her that the Aruza Valley is the home of many lions and a dangerous place to go on her own, Jane heads there in her jeep to study the red river hog. While following some tracks she stumbles in the mud and falls down in the riverbank striking the back of her head on a rock knocking herself out. As she slowly regain consciousness, she opens her eyes, rubs them and discovers that she cannot see anything. She reaches into her back pack, pulls out her radio only to find that it too does not work. Blind, alone and without a radio in an area known to be full of lions, Jane must compose herself and find shelter until someone can find her. While Jane is stumbling around the river, Roger tries to reach her by radio. When he gets no response he finds Tarzan and tells him that he feels that Jane is in trouble. Tarzan and Cheetah rush off, swinging through the jungle, heading for the Aruza Valley. With a lion stalking her , Jane continues her aimless wandering taking her to the edge of a Fire Field, a dangerous rocky area full of erupting geysers. Using a stick she picked up, Jane feels her way along a trail and discovers a cave, its entrance partly covered by a thorny bush. As the lion gets loser, Jane crawls into the cave and pulls the bush in front of the entrance. The lion, now at the mouth of the cave, starts pulling the bush away while Jane tries to keep it at bay by poking her stick at him through the bush. As this is going on, Tarzan and Cheetah find Jane's' radio at the riverbank and follow her tracks to the cave. Just as the lion is about to enter the cave, Tarzan arrives and orders the lion to leave. Tarzan picks Jane up and carries her to safety through the very dangerous Fire Field which is now erupting with full force. They arrive safely back at camp where Dan flies Jane to Bandali to see a doctor. When they return several days late, Jane's vision is beginning to return. It was only temporary blindness and everything will soon return to normal.