Chiana discovers that her brother is dead, but when she tries to talk to John he's distracted and gives her the brush off. Upset, she leaves Moya in Aeryn's Prowler and lands on a Royal Cemetery planet where clans of young people live in underground caves. In the caves is a deep pit at the bottom of which is a sonic net that uses the sound of the jumper's voice to generate sound waves to cushion their fall.
The clans live a highly ritualised life, and when they are 22 they jump into the pit in silence and die, which they call Taking the Stone. John discovers this is because there is a lot of radiation in the caves, which the pit amplifies, and after 22 cycles they begin to suffer radiation poisoning. He explains the radiation to them but the clans vote to remain in the caves and continue their ways rather than moving to the surface where they could live longer and healthier lives.