"Remember what curiosity did to the cat."
Lion-O and Snarf are strolling through a field of tall grass when they come across a giant metal box covered with the words DANGER and IPCF, with sounds like someone calling for help inside. Against Snarf's advice, Lion-O decides to open it. The three prisoners inside immediately rush past him and disappear, although one does take the time to steal his sword.
A Human Alien named Mandora ("Evil Chaser, First Class") quickly drives up, royally pissed at the "inexperienced oaf" who just released the criminals she was about to transfer to prison. She conscripts Lion-O to help her round up the three escapees: the Walking Wasteland Plutar, the robot Burnout, and the pickpocket Quick-Pick. They round up the first two after minor skirmishes, but their hunt for Quick-Pick is derailed when they're all captured by the Mudhogs (neither they nor the audience ever figures out why, presumably because they're the only race in the entire series who doesn't speak English). One "Thundercats, HO!" later, though, and the Thundercats make quick work of them, too.
And that's the story of how curiosity almost killed the cat.
This episode provides examples of:
- Action Girl: Mandora
- Affectionate Pickpocket: Quick-Pick helps Lion-O and Snarf up, stealing the sword and the latter's coin purse in the process.
- Bait-and-Switch:Living Ooze: Who dares to pollute my streams and kill my trees? That's my job!
- Beneath the Earth: Quick-Pick and Mandora get dragged underground by the Mudhogs.
- Card-Carrying Villain: Both Plutar and Living Ooze openly take pride in their ability to pollute and destroy.
- Curiosity Is a Crapshoot:Lion-O: I made a fool of myself because of my curiosity.
- Distressed Dude: Mandora saves Lion-O and Snarf when they're trapped by the Living Ooze.
- Don't Touch It, You Idiot!: Snarf warns Lion-O that when a box says DANGER on every side, you should probably stay away instead of opening it.
- Drives Like Crazy: Lion-O drives Mandora's bike as if he thinks he's supposed to hit every tree in his path.
- Enemy Mine: Lion-O, Mandora, and Quick-Pick are forced to team up when they are all captured by the Mudhogs.
- Eviler than Thou: As soon as Plutar and the Living Ooze meet, they start arguing over which one of them is better and quicker at spreading death and destroying life!
- Eye Beams: Mandora's are the only thing that distinguishes her from Homo sapiens.
- The Faceless: Mandora's never seen without her helmet covering the upper half of her face.
- Fire-Forged Friends: Mandora has zero respect for Lion-O, at first (understandable, given how massively he screwed up when she first met him), but grows to admire him as they fight together, eventually concluding he'd make a great Evil Chaser.
- Full-Boar Action: The Mudhogs are Pig Men.
- Giving Them the Strip: Mandora removes her uniform to escape the Living Ooze. (Sorry, fanboys — she's wearing a leotard underneath.)
- A Handful for an Eye: Mandora takes out Burnout by shooting goop in his "eyes" with her boomerang, causing him to blindly skid into water.
- Heel–Face Turn: After Quick Pick helps defeat the other criminals, Mandora decides to ask that he be paroled and he becomes her assistant.
- Hover Bike: Mandora drives a flying motorcycle that can also travel through space.
- Lesser of Three Evils: Among the three, Quick-Pick isn't as evil or dangerous as Plutar and Burnout.
- Make Them Rot: Plutar has this power and revels in it.
- Muck Monster: The Living Ooze.
- Mundane Made Awesome: Mandora curb stomps Plutar and the Living Ooze with a ray gun that shoots a shiny, white substance. Wow, must be some fancy, high-tech, super ammo she's packin' there!Lion-O: What is in that gun?Mandora: An ancient formula, now a closely guarded secret. It used to be called "soap."
- Mundane Utility: Mandora has Eye Beams, but she never uses them in combat, only for repairing a weapon.
- Names to Run Away from Really Fast: As Lion-O puts it, the Living Ooze certainly doesn't sound like "a place anyone would visit."
- Nice Job Breaking It, Hero: Lion-O releases what he thinks is someone in trouble. Turns out they were the bad guys, and they were supposed to be locked up.
- No Waterproofing in the Future: Burnout the robot is captured after he shorts out due to getting wet.
- Offscreen Villainy: According to Plutar, "Where I have been, whole planets die!" He's not one of the galaxy's most wanted criminals for nothing!
- One-Way Visor: Mandora has a helmet of the concealing-eye-slit style.
- Prison Escape Artist: Quick-Pick
- Redemption Quest: This is what Lion-O is on, helping Mandora round up the criminals he was stupid enough to release.
- Reflexive Response: When he first comes face to face with Plutar, Lion-O instinctively reaches for his sword, only to remember it's not there.
- Slippery Skid: The Living Ooze causes Mandora's bike to skid out of control when she tries to land.
- Space Police: Mandora's organization, the Interplanetary Control Force.
- Touch of Death:Mandora: Everything Plutar touches eventually dies.
- Ungrateful Bastards: Sure, it wasn't a good thing, but from the criminals' perspective, Lion-O is the one who freed them. That doesn't stop Plutar and Burnout from attacking him later, or Quick-Pick from robbing him.
- Vader Breath: Plutar wheezes when he talks.
- Villain Team-Up: After arguing a bit when they meet, Plutar and the Living Ooze agree to work together to ambush Mandora and her comrades.
- Walking Wasteland: Plutar.
- Weakened by the Light: The Thundercats don't need to shoot any weapons at the Mudhogs, just shine a bright light in their eyes.
- Would Hit a Girl: Plutar almost kills Mandora — fortunately, she was able to blast him before he could touch her.
