Gargantia on the Verdurous Planet

Deep Sea Secret (1x9)

Air date: Jun 02, 2013

Ledo and Chamber go deep sea-diving to exterminate Earth's Hideauze. After an intense battle, they discover a Hideauze citadel at the bottom of the sea, and inside, ancient video footage of the Earth's former civilization, the race to escape into space, and a secret that blows Ledo's mind!