Defenders of the Earth - Season 1 - Eps 53: Call of the Eternals
Ming sends a look-alike Defender ship to provoke the Beacon of the Eternals- a computer operated ship searching for a long lost benevolent society- which thereby releases its three Guardian Robots to retaliate against our heroes. The Guardian Robots are the most powerful form of robot in the known universe. When Flash destroys one of them, its strength transfers to the other two, increasing the danger to both the Defenders and the Earth. With one of the two remaining robots hot on their tail, L.J., Kshin and Zuffy fly to New York to retrieve Mandrake and Lothar, while Flash, Rick and Jedda lock the third robot in a force (stasis) field surrounding Monitor. In New York Mandrake defeats the second robot through a brilliant illusion. However, this was Ming's plan. The final Guardian doubles in size, draining Monitor of its power source and transforming itself into an unbeatable machine. Rick conceives a plan which the Defenders put into action- a homing torpedo is outfitted with a mock signal from the Eternals and launched into a black hole, thereby tricking the Beacon into sending the final robot to investigate the signal. The final robot is destroyed and our heroes and the Earth are safe from Ming's grasp- temporarily.
About Defenders of the Earth

Title: Defenders of the Earth
First Air Date: 1986-09-08
Last Air Date: 1986-12-05
Status: Ended
Rating: 7.5/10 (from 83 votes)
Language: EN
Seasons: 2
Total Episodes: 65
Network: Syndication
Genres: Animation, Action & Adventure
Production Companies: Marvel Productions, King Features Syndicate
Synopsis
Defenders of the Earth is an American animated television series produced in 1986, featuring characters from three comic strips distributed by King Features Syndicate—Flash Gordon, The Phantom, and Mandrake the Magician—opposing Ming the Merciless in the year 2015. Supporting characters include their children Rick Gordon, Jedda Walker, Kshin, Mandrake's assistant Lothar, and Lothar's son L.J. The show lasted for 65 episodes; there was also a short-lived comic book series published by Star Comics, created by Gerry Conway, Ross Andru and John Romita, Sr.. The closing credits credit Rob Walsh and Tony Pastor for the main title music, and Stan Lee for the lyrics. The series was later shown in reruns on the Sci Fi Channel as part of Sci Fi Cartoon Quest.
Cast

Buster Jones

Peter Mark Richman

Loren Lester

Peter Renaday

Sarah Partridge

Lou Richards

William Callaway

Hal Rayle

Ron Feinberg

Diane Pershing