On a volcanic island near the Kingdom of Hetvia rules Count Dakkar, a benevolent leader and scientist who has eliminated class distinction among the island's inhabitants. Dakkar, his sister Sonia and her fiance, engineer Nicolai Roget have designed a submarine which Roget pilots on its initial voyage just before the island is overrun by Baron Falon, despotic ruler of Hetvia. Falon sets out after Roget in a second submarine and the two craft, diving to the ocean's floor, discover a strange land populated by dragons, giant squid and an eerie undiscovered humanoid race.

Andre Dakkar

Sonia Dakkar

Nikolai Roget

Falon

Mikhail

Anton

Dmitry

(uncredited)

(uncredited)

Underwater Creature
October 5, 1929

Andre Dakkar

Sonia Dakkar

Nikolai Roget

Falon

Mikhail

Anton

Dmitry

(uncredited)

(uncredited)

Underwater Creature

