It is an updated version of the 20,000 Leagues Under the Sea walkthrough attraction that was at Disneyland in Anaheim, CA in the early 1950s, based upon the film of the same name.

Although guests may believe they are visiting the submarine seen in the lagoon, the 'underwater tunnel' leads them into a show building hidden by tall green bushes.

It began with the organ playing Johann Sebastian Bach'sToccata & Fugue in D Minor, and Captain Nemo giving a short speech about his ocean kingdom.

Then, the window opened for guests to witness the ocean depths, until a giant tentacle hit the glass.

[3] Disney Imagineer Tom Sherman designed the attraction and created many concept sketches and models.