A huge sea monster has attacked and wrecked several ships from beneath the sea.

Professor Arronax bravely joins a mission to hunt down the beast.

He goes aboard the Nautilus, a secret submarine helmed by the mysterious Captain Nemo.

At first, the mission is exciting, as Nemo takes the ship on a voyage around the underwater world.

But when things start to go wrong, Arronax finds there is no escape from the Nautilus -- he is now Captain Nemo's captive, 20,000 leagues under the sea!