In the story, Rikki-Tikki-Tavi is a mongoose. When a flood washed him away from his home, he is adopted by Teddy and his family. While exploring the garden, he meets Nag and Nagaina, two deadly cobras. Later that night, he overhears the cobras' plot to enter Teddy's house and kill his family. When Nag and Nagaina get inside, Rikki attacks and kills Nag in Teddy's bathroom. The next day, Rikki finds Nagaina's eggs on the ground and begins crushing all of the eggs except for one. When Nagaina threatens to kill Teddy, Rikki distracts her by threatening to destroy her last egg. Then, Rikki chased Nagaina into her hole in the garden and kills her. From then on, Teddy's family hailed Rikki-Tikki-Tavi as a hero for saving them from the two deadly cobras.