In the first episode of the six-part story "The Web Planet," the Doctor and his traveling companions attempt to investigate an unknown force that has been consuming space vessels. They soon discover the source of this phenomenon when the TARDIS is sucked into the atmosphere of the planet Vortis. Almost immediately, the travelers are caught in the middle of a power struggle between two tribes of insectoid creatures: the ant-like Zarbi and the butterfly-like Menoptera. Written by Bill Strutton, episode one of "The Web Planet" first aired on February 13, 1965. ~ Hal Erickson, Rovi