We're now back with Arthur and Bedevere who are accosting an old crone by saying "ni" to her because she won't tell them where to find the shrubbery they so desperately need.
Then they conveniently meet Roger the Shrubber.
But the Knights Who Say Ni are no longer the Knights Who Say Ni; they are the Knights That Say Ekki-Ekki-Ekki-Ekki-Ptang. Zoom-Boing. Z'nourrwringmm and they not only want a second shrub but demand that Arthur cut down the mightiest tree in the forest with a herring.
Robin shows up, and his minstrel's still singing about how much of a coward he is.
Together, Bedevere, Arthur, and Robin defeat the Knights Who Until Recently Said Ni by accidentally saying the word they cannot tolerate: "it."