Daggett really needs to use the bathroom, though one of the bathrooms in the dam isn't working and Norbert is keeping the remaining bathroom occupied. Daggett becomes upset because he doesn't know what he is supposed to do, though he knows he needs to find a bathroom quickly.
Dag's testing the toilet of what he calls it "The Big Unknown". Norb comes upstairs and to his shock, notices that Dag's using more items to flush down the toilet. Norb then shows Dag a poster of an important event called "Hair Just Righty Day". Dag claims his hair is always just righty. Norb asked Dag for his comb and hairbrush but Dag says he already flushed them. Dag then wonders what to flush next to the Big Unknown. Norb leaves in disappointment saying "I nominate you".
Later, after attempting to flush a mime by force, Dag inadvertently clogs the toilet. He's amused by the blue color and the fresh scent, until he becomes queasy from his bladder from the sight of the river of toilet water filling the bathroom. Dag runs out and knocks on Norb's bathroom door and pleads to use his bathroom, but Norb is busy fixing his hair. Dag tries to convince him that the "mime is stuck in the un-k-nown". Norb doesn't believe him as he suggests "you only get to break one toi-toi a day" and tells him to hold it until he is finished. Dag goes crazy and says "I'm gonna burst a gut or something!" and falls down the stairs.
Dag goes into more bladder pains after seeing water: dripping from a kitchen faucet, a waterfall roaring from the lake, Barry, in a funky hairdo and waving to Dag, hosing his flowers in the garden. Norb continues to try more hairdos but he still says they are not all "just righty". Dag, still going crazy, goes to his bathroom only to see the mime coming out of the toilet. Dag attacks him, which makes him break the toilet by accident. Water begins to spray on him turning him blue until Dag tries to fixing the toilet but to no success - water spews out.
As Norb continues to get his hair "just righty", he tries to fix it with a plunger, making the water stop gushing out but only for the float to attack him. Dag fights it and fences it with a toilet handle until more water gushes out. As Norb continues to do his hair, he sees his toilet suck up his accessories like a vacuum cleaner and him. Norb checks out to sees what is going on. Seeing Dag fight his own toilet, Norb flushes his making the water rain down on Dag but also sucked Norb's head and turning his hair blue. Norb panics and rushes to the mirror but as he checks it out, he seems to like it saying "Now that's just righty".
As Dag rushes with a mallet yelling "Die, potty, die!", more water gushes out of Norb's toilet. Norb decides to take his toilet seat for a touch-up. He goes downstairs and freaks out seeing the entire dam flooded. Dag, still fighting the float on a canoe, catches up with Norb. Dag is about to use Norb's toilet seat but Norb takes it away to use it for his new hair-do as a styling commode. Dag, still in bladder pains, begins to shake the boat. Dag says he will head for the pond if Norb does not give it back to him. Norb stops him and tells him he will fix his toilet. They swim underwater to Dag's bathroom. Norbert wiggles the toilet handle and the water stops gushing out. Dag then flushes the toilet only to suck up everything in the water including the two beavers. They head for the roof, but the entire dam sinks to the bottom into the giant whirlpool. Norb yells out "This is it! We're going down!", followed by Dag yelling out "Into the, bum-bum-bum, Big Unknown - I mean, Un-k-nown!"
A moment later, Wolffe D. Wolf, in a funky hairdo sees a plunger on the ground and bubbles arising to the surface. Wolffe saves the beavers and releases them, but gets spooked from the sight of the beavers' bad hairdo. Norb yells at Dag for flushing and messing up his hair, that he was "getting his hair just righty!". Dag tells him "But your hair is always just righty!" making Norb feel confident. Norb picks up his toilet seat and allows Dag to use his toilet. Dag says he doesn't need to anymore "thanks to the Big Unknown". Norb looks stunned and says "You let 'er rip in the Big Unknown?!" Dag replies "Ooh, yeah". The whole lake is shown with giant green spots all over as their dam rises up to the surface.
- The episode title is a play on the last name of French painter Henri de Toulouse-Lautrec.
- Star Wars - One of the hairdos Norb tried out throughout the episode is similar to Princess Leia's.
- "Rock the Boat" - an instrumental cover of The Hues Corporation's 1974 hit is heard when Norb and Dag's dam is flooding.
"Act Your Age"
"Pack Your Dags"