The Book of Omens
The Book of Omens - Title Card.png
Episode 4.20
Original Airdate September 29, 1989
Writer(s) William Overgard
Previous Episode Well of Doubt (episode)
All Episodes Episode Guide

The Book of Omens is the final episode from the original series of ThunderCats. Written by William Overgard, it originally aired on September 29, 1989.

ThunderCats Bullet Point.png Summary[edit | edit source]

The key to the Book of Omens is finally solved and it is unlocked. All of the team must pass different tests to save the planet, and Lion-O faces many trials within the book to prove himself once and for all as Lord of the ThunderCats.

ThunderCats Bullet Point.png Story[edit | edit source]

When violent geological disturbances threaten to rip apart New Thundera, Panthro and Lion-O decide to consult the Book of Omens for a solution. After using the Key of Thundera to unlock the book, the duo learn from the Guardian of the Book of Omens that the way to stop the imminent self-destruction of the planet is to present certain artifacts to specified locations within a fixed period of time. The final step would be to present the Key of Thundera to the Guardian himself. If this is accomplished, then the destructive and hostile places on New Thundera would transform into peaceful and productive areas. If the ThunderCats fail, then they will be frozen in time while the planet self-destructs.

After Lion-O and Panthro leave the chamber to make preparations and inform the other ThunderCats, Mumm-Ra, who had been spying on the ThunderCats by disguising himself as a scarab, changes back to his true form. He then takes the Key of Thundera and the Book of Omens and flies off to his pyramid with them.

The ThunderCats head out to the assigned locations, carrying the respective artifacts. Cheetara and Lynx-O, fly the ThunderStrike to the Caverns of Cold with the Tile from the Fountain. Snarf takes the Gem Light and accompanies Panthro in the Feliner to the Mountains of the Moon. Bengali and Snarfer pilot the HoverCat to the Baleful Swamp with the Golden Oar, and the ThunderKittens head to the Iron Glades in the Whisker, carrying with them the Ancient ThunderCat Flag.

When Lion-O goes to carry out his task of presenting the Key of Thundera to the Guardian, he is shocked to discover that both the key and the Book of Omens are missing. Immediately suspecting Mumm-Ra, he rushes to the Black Pyramid. Inside his lair, Mumm-Ra uses the Key of Thundera to enter the book, despite the Ancient Spirits of Evil forbidding him from doing so. Lion-O, who had just arrived at the scene, also enters the book using the Sword of Omens.

Inside the Book of Omens, the Guardian, after freezing all the ThunderCats, tells Lion-O that he must face and defeat Mumm-Ra in unarmed combat and reclaim the Key of Thundera. After an intense battle, Lion-O emerges the victor but Mumm-Ra summons the Ancient Spirits of Evil to send their champion, Pyron. This mysterious warrior proves to be a much tougher adversary for Lion-O, but the young lord uses the Dragons to incinerate Pyron with their fiery breath.

Having rightfully reclaimed the Key of Thundera, Lion-O presents it to the Guardian at the 24th hour. The Guardian tells Lion-O to summon the ThunderCats to announce his victory. Lion-O does so and the black panther in the ThunderCats signal comes to life and unfreezes all of the ThunderCats. In turn, the ThunderCats present their artifacts, and the once hostile locations of New Thundera are transformed to peaceful areas.

ThunderCats Bullet Point.png Characters[edit | edit source]

ThunderCats Bullet Point.png Vehicles[edit | edit source]

ThunderCats Bullet Point.png Locations[edit | edit source]

ThunderCats Bullet Point.png Trivia[edit | edit source]

  • This is the last episode of the 1980s ThunderCats cartoon series.

ThunderCats Bullet Point.png Goofs[edit | edit source]

  • The Baleful Swamp, which was shown in the earlier episode "Totem of Dera" to be on Third Earth, in this episode is shown to be on New Thundera.

ThunderCats Bullet Point.png Notable Quotes[edit | edit source]

Panthro: This one is no regular earthquake. The whole planet is being destroyed.

Lion-O: My job now is to enter the book and present the key to the guardian at exactly the twenty fourth hour.

Mumm-Ra:' I now have the means to destroy the ThunderCats!

ThunderCats Bullet Point.png Media[edit | edit source]

This episode was released on the following media:

DVD[edit | edit source]

ThunderCats Bullet Point.png Episode Screenshots[edit | edit source]

ThunderCats Bullet Point.png External Links[edit | edit source]

ThunderCats 1980s - Episode Guide - Season 4
Return to Thundera - Part I | Return to Thundera - Part II | Return to Thundera - Part III | Return to Thundera - Part IV | Return to Thundera - Part V | Leah | Frogman | The Heritage | Screwloose | Malcar | Helpless Laughter | Cracker's Revenge | The Mossland Monster | Ma-Mutt's Confusion | The Shadowmaster | Swan Song | The Touch of Amortus | The Zaxx Factor | Well of Doubt | The Book of Omens Tygra.png
Seasons Season 1 | TV Movies | Season 2 | Season 3 | Season 4 | Full Episode List
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