Courage discovers a stone slab near the waterpump of the farmhouse. The stone slab turns out to be a relic, stolen from a Pharaoh's tomb, that is worth one million dollars. Eustace refuses to return the stolen slab without payment, and the entire family faces the wrath of its three curses as a result.
In the dead of the night, after stealing a stone slab from the tomb of King Ramses, two feline grave robbers are fleeing from the scene of the crime in their car. Pursued by the police, the duo decides that the best course of action is to hide the slab, and return to its location once the authorities have given up the chase in order to retrieve it (for the sake of concealing any incriminating evidence). They pull over to bury the slab at the nearest landmark in sight, which is the Bagge's water-pump. As they reenter their vehicle in order to escape, they are confronted by King Ramses himself, who demands that his slab be returned lest the thieves suffer his curse. The confused thieves, unaware of the curse, do not have a chance to react before they are surrounded by a swarm of locusts, which quickly devour both them and the car. Puzzled by the scene, Courage watches with curiosity from the farmhouse, but does not investigate further.
The next morning, Courage cannot contain his curiosity and unearths the slab. The slab contains symbols of Ramses, water, a record player, and locusts. Courage shows it to his owners, but Eustace dismisses the slab as "garbage" and tosses it out the window. However, Eustace's opinion changes after learning from the Nowhere Newsman that the stolen artifact is worth one million dollars. Immediately, Eustace contacts the Nowhere Newspaper to place an ad for the slab, despite Muriel's condemnation of his behavior. Professor Frith arrives and tries to reclaim the slab, but Eustace refuses to give it up for free.
That night, the ghost of Ramses returns, and this time threatens the Bagges. He orders Eustace to return the slab or he would be visited by three "plagues", each worse than the last. Eustace, believing that the ghost is the professor in disguise, gives the ghost his customary response of "What's your offer?" and then clams the door on the ghost when the ghosts repeats himself. The ghost unleashes the first plague. The representative symbol on the slab, the rain, disappears, and the house subsequently begins to fill up with water. While Muriel is drowning, Eustace uses his snorkel gear. Courage pulls a drain stopper in the basement and all the water drains out from the house thus defeating the first plague much to the ghost's annoyance. Unfazed by the ordeal, Eustace again refuses the ghost's request asking for an offer, initiating the second plague. Again, the representative symbol on the stone slab, the record player, disappears. A skipping record that repeatedly blares "King Ramses, the man in gauze," permeates the air, causing the family audible pain. Eustace alleviates the noise by plugging his ears using cotton, but leaves Muriel suffering. Courage finds the source of the noise behind a boulder, destroying the phonograph with a baseball bat to stop the racket. King Ramses once again demands the return of his slab. Muriel insists that Eustace return the slab, but Eustace still refuses to do so without getting paid. The ghost then unleashes his third and final plague: the locusts. The final symbol disappears from the slab, and the insects begin to devour the house starting from the roof. As the house is destructed by the locusts, Muriel prepares food as a stress relief tactic. Courage and Eustace wrestle over the slab. Eustace finally gives in once he realizes how close they are to being devoured, allowing Courage to toss the artifact toward Ramses, which ends the curse. However, Eustace reclaims the slab after the locusts had left and taunts Ramses, thinking that he, since he used three different plagues, is now powerless. Annoyed, Ramses simply reuses the third plague by summoning the locusts again, and Eustace is devoured.
Within the carnage in the wake of the locusts, Muriel is rocking Courage as usual, watching TV. On TV, Professor Frith explains that the slab has been returned to the Pharaoh's tomb and will remain protected for all time. The end of the episode shows the tomb of King Ramses, where Eustace has now apparently replaced Ramses on the slab, as punishment for his greed.
- Eustace: Well, judging by the markings and the obvious age of the relic, I'd have to say it would be... garbage! (he tosses the slab out of house)
- Muriel: Eustace!
- Eustace: Garbage! From King Garbage! Of the Garbage Dynasty! Stupid dog, always bringing garbage into the house.
- King Ramses: Return the slab or suffer my curse.
- Eustace: What's your offer?
- King Ramses: Aw, come on!
- Professor Frith: At last, the illiterate cursed slab has been returned to King Ramses' crypt where it will remain buried in antiquity for all time.
- First (and only) appearance of King Ramses, first appearance of Professor Frith.
- When Courage transforms into a boat, a sailor version of the Freaky Fred music can be heard.
- King Ramses does not give the cat thieves three chances to return the slab, unlike the Bagges.
- This episode was played at the end of the VHS of Scooby-Doo and the Alien Invaders.
- Courage only has one line of dialogue in this episode, not counting his yelling and screaming.
- When Muriel runs away from the locusts (screaming), it shows her running into what is supposed to be the kitchen, but what the animation shows is clearly the backyard.
- While locusts are frighteningly voracious, they only eat plant life, not living creatures and inanimate objects, as this episode suggests.