ThunderCats - Season 1 - Eps 21: Dr. Dometone
An old scientist seeks the Thundercats to help him save the oceans of Third Earth. Long ago, a crack was made in the bottom of the ocean which caused the water to drain into the earth's core. Dr. Dometone created a plug which sealed the hole in the ocean, and saved Third Earth from destruction. Now, an evil miner, Scrape, has come to remove the plug and mine the rock that is found on the bottom of the ocean. The Thundercats join Dr. Dometone and his frog-like robot, Herkie, to save the planet from total destruction.
About ThunderCats

Title: ThunderCats
First Air Date: 1985-01-23
Last Air Date: 1989-09-29
Status: Ended
Rating: 8.2/10 (from 1031 votes)
Language: EN
Seasons: 5
Total Episodes: 130
Network: Syndication
Genres: Animation, Sci-Fi & Fantasy, Action & Adventure, Kids
Production Companies: Rankin/Bass Productions, Lorimar Telepictures
Synopsis
The inhabitants of the planet Thundera evacuate just before it is destroyed. They were pursued by a band of mutants. All but one of their escape ships was destroyed. Only a small group of Thunderans (Thundercats) remained. With only half engine power, the group, which was led by Jaga, had to set a course for the nearest planet. Jaga commanded their ship while the other seven were in their stasis tubes. Jaga died on their journey to Third Earth and their ship crashed there. Soon they made friends with various groups in the area and they designed a fortress. Mumm-Ra the centuries-old embodiment of evil, along with the mutants that destroyed the rest of the Thunderans are a constant threat. But Lion-O, the new leader of the Thundercats, with his weapon the "Sword of Omens" will help the Thundercats to have a standing chance.
Cast

Larry Kenney
Lion-O / Jackalman (voice)

Peter Newman
Tygra / WilyKat / Monkian (voice)

Earle Hyman
Panthro (voice)

Lynne Lipton
Cheetara / WilyKit (voice)

Earl Hammond
Mumm-Ra / Jaga / Vultureman (voice)

Bob McFadden
Snarf / Slithe (voice)

Gerrianne Raphael
Pumyra (voice)

Doug Preis
Alluro (voice)