Hades plans a party Mt. Olympus will never remember, planning to seize control by tricking the other Olympians into a dip in the Pool of Forgetfulness. Can Hercules and the uninvited Trivia find a way to restore the others' memories before Earth destroys itself in chaos?
This episode includes examples of the following tropes:
- All Your Powers Combined: At one point, Hercules confronts Hades using the tools of all the other Gods, although he is only able to delay Hades until the other Gods regain their memories and confront him directly.
- Amnesia Episode: Hades' plot du jour involves tricking the other Olympians into swimming in Lethe water, which causes memory loss.
- Batty Lip Burbling: During "Lethe Water on the Brain", Zeus does a motorboat impression with his lips to show that all the Olympians are loopy thanks to the Pool of Forgetfulness.
- The Bore: The other Olympians find Trivia incredibly annoying due to his constantly spouting off trivial information about anything related to the issue at hand.
- …But He Sounds Handsome: An accidental example; Hades calls in Hephaestus, who has lost his memory, to unlock Olympus' gates. Finding it difficult, Hephaestus mentions that whoever made them must have been really skilled. Hades doesn't find the irony amusing.
- Establishing Character Moment: Trivia first appears holding up a bowling game by interjecting a fun fact about it and then achieving a perfect strike with his knowledge of spin. This sums up his boring personality, the other Olympians' exasperation with him, and the importance of the knowledge he possesses.
- Near-Villain Victory: Hades comes extremely close to winning in this episode, and the only reason he doesn't take over Olympus is because Pain and Panic accidentally lock him out.
- Putting the Pee in Pool: When Hades catches him trying to leave, Zeus claims he was looking for the bathroom. Hades flatly tells him to get into the pool, which Zeus misinterprets. He questions if that is sanitary.
- Tempting Fate: Hades tells Pain and Panic to leave Trivia off the guest list, scoffing at the idea that he could do anything. He ends up destroying the whole plot.
