Calvin and Hobbes crash their wagon in a lake, as is the norm for them. However, unbeknownst to them, a tiny little robot has taken to Calvin's pocket, directed by some mysterious force to spy on them. Said mysterious force is soon shown to be a man, giggling madly and predicting that he'll soon have the most powerful energy source in the universe.
The duo return home, and Calvin is sent upstairs for a bath, fantasizing about Spaceman Spiff being forced into the Lava Pit of Doom for not handing over the formula for an immortality serum. After he's dropped in, the aliens soon find that he's already taken the formula, making him completely immortal. Unfortunately, before the tale can continue any further, the power on Calvin's house goes out. His parents try to find the source of the blackout, and Calvin dries off and heads to his room.
The MTM states that there weren't any power fluctuations, and Hobbes walks in, rather angry at his ride in the washing machine being cut short. After the two dry off, the MTM finds that something is absorbing all the electricity from the house, and his attempt to capture it leaves it bereft of energy, making him useless. Calvin and Hobbes manage to capture the robot in a jar, though, and they take it to Sherman's to analyze.
Sherman finds that its primary directive is to steal electricity, and manages to track down its maker to be somewhere near Las Vegas. While they talk, however, the robot manages to break the jar and escape, sapping the lab's electricity in the process. He gets out his flashlight, which is quite powerful, and the three try to get out of the lab.
Meanwhile, Andy's computer game is shut off by the same power outage, and he gets Socrates to help Sherman out of the lab. Socrates happens to have a generator, and he uses it to power the house and get down in the lab. There, they get up to speed, and the group flies off to Vegas in Calvin's box.
As all this happens, Calvin's dad desperately tries to prove his technical know-how by tearing all the wires apart, getting himself shocked in the process.
The group lands in Vegas, making comments on the sights there, and Calvin cloaks the box. Soon, they come across their destination, which appears to be a normal blue mailbox. Hobbes finds that by touching a loose bolt, you're teleported to the villain's underground lair. The other four soon follow suit.
Inside the lair, the quintet try to sneak into the lair, but are soon discovered by the Lightning Man, who turns on every light in the lair and introduces himself. He quickly reveals that he knows a lot about the heroes, and reveals his plan - he aims to stop the heart of everyone in the world with Sherman's electricity! The heroes quickly point out the flaws in his plan, and after some negotiating he eventually gets fed up and leaves himself open to an attack from Hobbes.
Sherman tries to hack into the computer, but it's missing a crucial bit of code that the robot has. Unfortunately, it's busy uploading the electricity to begin the Man's plan. As he gloats, two familiar faces show up - Jack and Dr. Brainstorm. The former sends a system update to the tiny robot, making it stop uploading the electricity, and he gets rid of it. He calls in the rest of the family, and Sheila reveals that the Lightning Man, aka Percy Lightningstorm, is her uncle.
Somewhat surprised by this development, the five heroes learn that their exploits tend to dominate Christmas dinner discussion, and Socrates lambastes Percy for "cheating off their papers". They leave to resume their family vacation, and everyone returns home.
Calvin finds, however, that Dad's attempts to fix the electricity have only screwed things up further, and his mom just gives up on dinner and calls in some pizza, much to his and Hobbes' delight.
- Anime Hair: The Lightning Man's hair apparently resembles a Hershey's Kiss and droops over his face.
- And Then What?: Calvin and company have this discussion with the Lightning Man, who wishes to kill everyone in the world. He relents by only killing half of them, but when Calvin remarks that it would leave enough for a rebellion, he changes it again to kill three-fourths of the world.
- Antagonist Title
- Apocalypse How: The Lightning Man aims for a Class 3A by giving everyone on Earth a heart attack at the exact same moment.
- Brick Joke: Socrates mentions a fat woman hogging the shrimp buffet while in Vegas. Much later, Mother Brainstorm mentions being at the shrimp buffet before finding Percy there.
- Brought to You by the Letter "S": The Lightning Man wears a "L" on his shirt.
- Complete Immortality: In Calvin's fantasy, the immortality serum appears to grant this, as Spiff climbs out of a lava pit completely unharmed (though slightly singed).
- Doom It Yourself: Calvin's dad tries to fix the electricity himself, with predictably horrible results.
- Doomy Dooms of Doom: The Lava Pit of Doom.
- Elaborate Underground Base: Lampshaded heavily once the heroes find the Lightning Man's lair.Hobbes: It's a lair! What is it with bad guys and lairs? Can't they just live in houses?
Socrates: Imagine a super villain living in a studio apartment in southeast central L.A. I wonder if they could afford the rent.
- Embarrassing First Name: The Lightning Man, aka Percy. Calvin has trouble not laughing at it when it's revealed.
- Huddle Power: Calvin and company do this when considering the Lightning Man's final plot.
- Immortality Seeker: The aliens in Calvin's fantasy.
- Latex Perfection: Referenced as Jack shows up:Andy: You better not be Frank wearing a rubber mask.
- Laughing Mad: The Lightning Man.
- Light Is Not Good: The Lightning Man.
- Luke, I Am Your Father: The Lightning Man, or Percy Lightningstorm, is Dr. Brainstorm's uncle. It's only really a surprise to the other characters, however.
- Nano Machines: The robot.
- Noodle Incident:Sherman: Nobody light any matches in here! I haven't gotten rid of the gas from the last experiment!
Hobbes: What gas?
Sherman: Don't worry. It's not toxic anymore.
- Socrates' generator was apparently needed for a prank involving a tree he found in the woods.
- Nothing Can Stop Us Now!: The Lightning Man declares this as his plan comes to a head.
- Pac-Man Fever: Andy's game involves "trying to defeat an evil wizard with his super-glowy sword thing that would free some sort of princess, which he then had to save from a dragon."
- Pre Ass Kicking One Liner: After a lengthy And Then What? discussion:The Lightning Man: OH, WHAT'S THE PROBLEM NOW?!
- Punny Name: Percy Lightningstorm.
- Shock and Awe: The Lightning Man, unsurprisingly.
- Tomato Surprise: The Lightning Man is Dr. Brainstorm's uncle.
- Unusually Uninteresting Sight: Lampshaded below.
- Viva Las Vegas!: The Lightning Man's lair is located in Vegas. No casinos are seen, though the story does point out the strange passers-by.Andy: There's a man in a sparkly leotard breathing fire on the sidewalk. You know, before I met any of you that would've freaked me out.
- Wham Line: As the Lightning Man's plan comes to fruition:The Lightning Man: NOTHING IN THE WORLD CAN STOP ME NOW!
Jack: Wanna bet?
Sheila: Know him?! Ha! He's our uncle!
- And then, not long afterwards:
- Who Dares?: The Lightning Man introduces himself with such a phrase."WHO DARES TO DARKEN THE LIGHTNING MAN'S DOOR STEP?!"