Ep. 8: Jean allies with Grandis gang to infiltrate compound and rescue Nadia from Gargoyle's submarine.
Aired on June 1, 1990

8
Jean teams up with the Grandis gang to infiltrate a compound and rescue Nadia. Their mission nearly succeeds until Gargoyle's submarine, the Garfish, corners them at the intake point. Just as hope fades, the Nautilus emerges from the ocean and attacks the Garfish, enabling the group to escape. Gargoyle then attempts to counterattack using the Tower of Babel, but the structure collapses and destroys his compound instead. The islanders are freed from captivity, while Gargoyle manages to flee the scene aboard a dirigible.
Episodes
- Ep. 4 · Jean, Nadia, and King are rescued by Captain Nemo's mysterious submarine, the Nautilus.
- Ep. 5 · Jean, Nadia, and King crash on an island and meet a young girl named Marie.
- Ep. 6 · Jean and Nadia infiltrate the island's secret factory complex to rescue Marie and King.
- Ep. 7 · Gargoyle forces Nadia to reveal the Blue Water's location while showcasing the destructive Babel tower.
- Ep. 8 · Jean allies with Grandis gang to infiltrate compound and rescue Nadia from Gargoyle's submarine.
- Ep. 9 · Nemo's Secret: The Nautilus Visit and Blue Water Discovery
- Ep. 10 · Grandis, Sanson, and Hanson attempt to clear mines for the Nautilus escape.
- Ep. 11 · New recruits join the Nautilus submarine crew
- Ep. 12 · The Nautilus visits an island where Jean meets Nadia and Grandis competes for Nemo's attention.