Pumm-Ra is the fifth episode of the original Thundercats series.
While out for her morning jog, Cheetara is drugged and captured by the Mutants as part of Mumm-Ra's plan. Mumm-Ra then transforms himself into a Thunderian named Pumm-Ra and when Cheetara regains consciousness, he tells her that he saved her from the Mutants. He also tells her that he too was a resident of Thundera and managed to escape its destruction by fleeing in a small spacecraft.
Cheetara takes Pumm-Ra back to Cats Lair where he tells his story to the rest of the ThunderCats. Lion-O is keen to induct Pumm-Ra into the ThunderCats but Panthro and Tygra are wary and decide to give Pumm-Ra a week's probation. That night, while the ThunderCats sleep, Pumm-Ra sabotages both the Cats Lair and the ThunderTank and also succeeds in stealing the Sword of Omens and the Claw Shield.
The next morning, Lion-O and Snarf are left to guard the Lair while the rest of the Cats go off to the Thundrillium fields. Pumm-Ra seizes this opportunity and signals the Mutants to attack. He himself tries to use the Sword of Omens against Lion-O but because it cannot be used for evil purposes, a bolt of lightning knocks it and the Claw Shield out his hands. The Mutants attack using the ThunderTank but the rest of the Cats arrive in time and drive them off.
Meanwhile, Pumm-Ra locks himself inside Cats Lair. Tygra suggests an alternative route into the Lair and he enters the Power Exhaust pipe into the fortress. The rest of the ThunderCats eventually manage to enter the lair and finding himself cornered, Pumm-Ra transforms back to Mumm-Ra and teleports back to his pyramid.
- In the scene where Tygra is telling Pumm-Ra that he is their guest, his right shoulder changes from his normal light grey to a dark grey for a few seconds.
- In the scene in which Lion-O is in the ThunderTank and trying to contact Panthro, the Claw Shield and Sword of Omens are both clearly visible on his waist even though at that point they were in Pumm-Ra's possession.
- Upon seeing the Sword of Omens, Pumm-Ra (Mumm-Ra) reacts with surprise that it is much smaller than when he last saw it even though he had already seen it in its short form in the earlier episode The Unholy Alliance
- While searching for the Sword of Omens, Mumm-Ra comes across an armory of gun-like weapons lying on a table even though none of the ThunderCats have ever been shown to carry or use such weapons.
- Pumm-Ra is shown sabotaging the controls of both the Cats Lair and the ThunderTank and yet he is able to use the Cats Eyes to first signal the Mutants and then fire its Laser beams while the Mutants are shown driving the ThunderTank.
- Even though Wilykit and Wilykat left with the rest of the ThunderCats to go to the Thundrillium fields, they are not seen when Lion-O summons the ThunderCats nor do they return to battle the Mutants. They only appear again towards the very end of the episode.
- Pumm-Ra is one of the four episodes (co)written by series executive Jules Bass, using the pseudonym Julian P. Gardner.
- This is the first time Tygra, Panthro, Cheetara, and Snarf saw Mumm-Ra. Previously, Lion-O had been the only Thundercat to actually see him.
- When Mumm-Ra transforms in this episode, the dialogue is altered: instead of "Ancient Spirits of Evil", he just calls them "Spirits of Evil", and instead of referring to himself as "this decayed form" he says, "this ancient body". After becoming Mumm-Ra The Everliving, he asks to be transformed into "Pumm-Ra, the puma of Thundera", his latest disguise for tricking the ThunderCats.
- Cheetara clocks in at 30 seconds to the mile on her morning jog. that means her average speed is 120 miles per hour.
- Moral Tygra:' "First impressions are often wrong. Trust takes time to grow".
Tygra: Although Lord Lion-O leads us, Jaga chose me to be the head of the ThunderCats council.
Jaga: The mystic Sword of Omens cannot be used for evil deeds! Attempt it and know the wrath of Jaga!
Mumm-Ra: [searching for a way into the ThunderCats' sword chamber] They have used an ancient Egyptian locking device, unknown for a thousand years. Unknown, except, to one who has LIVED for a thousand years.
Panthro: Cheetara late? That's like the sun forgetting to set.
Panthro: I told Lion-O that he could have the tank this afternoon.
Tygra: Can he drive it?
Panthro: He took to it like a fish to water.