The Knights who say "Ni!" Audio (US) , also called the Knights of Ni, are a band of knights encountered by King Arthur and his followers in the film Monty Python and the Holy Grail. They demonstrate their power by shouting "Ni!" (pronounced "nee"), terrifying the party, whom they refuse to allow passage through their forest unless appeased through the gift of a shrubbery.
The knights appear silhouetted in a misty wood, wearing robes and horned helmets; their number is never apparent, but there are at least six. The leader of the knights, played by Michael Palin, is the only one who speaks to the party. He is nearly double Arthur's height, and wears a great helm decorated with long antlers. The other knights are large, but of human proportions, and wear visored sallet helmets decorated with cow horns. The knight explains that they are the "keepers of the sacred words 'Ni', 'Peng', and 'Neee-Wom'." Arthur confides to Sir Bedivere, "those who hear them seldom live to tell the tale!"
The knights demand a sacrifice, and when Arthur states that he merely wishes to pass through the woods, the knights begin shouting "Ni!", forcing the party to shrink back in fear. After this demonstration of their power, the head knight threatens to say "Ni!" again unless the travelers appease them with a shrubbery; otherwise they shall never pass through the wood alive. When Arthur questions the demand, the knights again shout "Ni!" until the travelers agree to bring them a shrubbery, which the head knight specifies must be "one that looks nice. And not too expensive."
In order to fulfill their promise to the Knights of Ni, the party visits a small village, where Arthur and Bedivere ask an old crone where they can obtain a shrubbery. The woman questions them, and Arthur admits that it is for the Knights who say "Ni!", whereupon she refuses to cooperate. Arthur then threatens to say "Ni!" to the old woman unless she helps them, and when she still refuses, begins shouting "Ni!". Bedivere has trouble saying the sacred word, which he pronounces "Nu!" until Arthur demonstrates the correct technique. As the crone shrinks back from their combined assault, they are interrupted by Roger the Shrubber, who laments the lack of law and order that allows ruffians to say "Ni!" to an old woman. Arthur obtains a shrubbery from Roger, and brings it to the Knights of Ni.