At Khalil Prison in Jerusalem, a new inmate, Robin of Loxley, is interrogated about the location of his king. When Robin feigns ignorance, he is tortured with “tongue looseners” and chained next to an elderly African man. The men break their shackles, liberate their fellow inmates and proceed to the coast, where the African man introduces himself as Asneeze. He tells Robin that his son, Ahchoo, is an exchange student in England, and asks Robin to look out for him when he returns home. Robin vows to comply, then swims from Israel to England. After renting a horse, Robin comes upon guards beating a young man, whom he identifies as Ahchoo. Robin rescues Ahchoo and they ride to Loxley Hall, Robin's home, just as it is wheeled away. When Robin demands an explanation, he is presented with an edict signed by Prince John that declares the property repossessed in lieu of payment for back taxes. As Loxley Hall is pulled from its foundation, Blinkin, the Loxleys' blind servant, remains inside on the toilet, unaware that the walls around him are gone. Although thrilled that Robin has returned safely from the Crusades, Blinkin reports the unfortunate news that Robin’s entire family, including his dog, goldfish and cat, have died. Giving Robin a locket Blinkin tells his master that his father wanted him to have it because it contains the key to “the greatest treasure in all the land.” As they leave the remains of Loxley Hall, Robin, Blinkin and Ahchoo are approached by a boy who is running away from the Sheriff of Rottingham and his men. The Sheriff claims the boy is guilty of hunting deer on the king's grounds, an offense punishable by death; but Robin informs the Sheriff that he has been fighting with King Richard in the Crusades. Humiliated by his speech impediment and his tactical blunders, the Sheriff retreats and the grateful boy returns home with the message that Robin will defend the people against injustice. Meanwhile, inside the king’s castle, young Marian sings longingly from her bath about finding true love when her maid, Broomhilde, advises her to get out of the tub before her chastity belt rusts. Marian wishes on a bluebird for the arrival of the man who possesses the key to her metaphorical heart. When the Sheriff warns Prince John of Robin's return, the prince visits the clairvoyant witch Latrine for guidance. She agrees to concoct a magic potion to stop Robin if Prince John helps her attract the object of her affection, the Sheriff. Riding through the forest, Robin, Blinkin and Ahchoo meet Little John, who demands a bridge toll, and Robin challenges him to a duel. After Robin knocks Little John from the bridge into the stream below, Little John thinks he is drowning, and when Robin helps him up, he thanks Robin for saving his life. Little John introduces his best friend, Will Scarlet O'Hara, who demonstrates his talent with daggers by pulverizing an oncoming arrow. When Little John explains that he must demand a toll because Prince John has robbed the people of their livelihood, Robin says he is plotting against the prince and plans to crash his party that evening. Little John offers to help, but Robin says the job will be easier done alone. At the party, the Sheriff flirts with Marian when Robin arrives, wielding a boar corpse as a gift. As Robin and Marian exchange seductive introductions, the Sheriff angrily stutters that hunting is illegal in the king’s forest, but Robin reminds Prince John that he has illegally usurped the king’s power in his absence. Robin warns that if the prince does not cease levying unjust taxes, he will lead the people in a revolt. When the Sheriff challenges him to a duel, Robin finds himself outnumbered against the Sheriff’s guards, but Ahchoo, Blinkin, Little John, and Will come to the rescue. During the fight, Robin and Marian declare their love for one another and despite an influx of armored troops Robin and his men are able to hold them off. Back in the forest, Little John introduces Robin to his newly formed army, but Robin is disappointed by the disheveled rabble, and as he attempts to rally the troops, they fall asleep. Ahchoo steps in and rouses them with revolutionary slogans. During their disastrous training routines, Robin and his Merry Men befriend Rabbi Tuckman, the wine seller and moyel, who informs Robin that Marian is longing for him. Meanwhile, at the castle, the Sheriff hires Mafioso Don Giovanni to eliminate Robin, and the Don tells him to lure Robin to the fair the following day with an archery contest. When the Sheriff warns that Robin is the best archer in the land, the Don claims his associate, Filthy Luca, will beat him and plans to have Robin killed by Dirty Ezio after the event. Marian overhears the meeting and rides into the forest with Broomhilde to warn Robin. Although Robin initially agrees not to attend the fair, he is tempted by the archery contest. Taking Marian aside, Robin asks for a kiss, but Marian tells him she is a virgin and he discovers her chastity belt. She describes a scroll that foretells the presence of a man with a special key to unlock it, and before the couple can kiss, Broomhilde interrupts and guides Marian back to the castle. The next day, Little John, Ahchoo, Will, and Blinkin arrive at the fair dressed as women. As the archery contest begins, Dirty Ezio waits in the tower, armed with a crossbow. Two archers, Luca and an old man, hit the bulls-eye in the first round, but after a successful second shot, the Sheriff announces that the old man is Robin in disguise. Robin takes off his mask and the crowd cheers, but after Luca splits Robin's arrow in two, winning the contest, the crowd cheers for Luca. As Robin aims for one last shot, the Sheriff motions for Dirty Ezio to kill him, but Blinkin catches Ezio’s arrow before it hits his master. When Robin’s second arrow obliterates the bulls-eye, the Sheriff calls for his arrest. Marian intercedes and promises to marry the Sheriff if Robin's life is spared. The wedding proceeds as Robin waits on the scaffold attached to a noose, in case Marian changes her mind. Before Marian says: "I do," Ahchoo shoots an arrow through Robin's noose, freeing him, and the Merry Men arrive to fight the guards. When the Sheriff takes Marian into the castle tower, he discovers her chastity belt and uses a jackhammer to break the lock. Robin and the Sheriff duel in a sword fight, but as the Sheriff attempts to cut his rival’s throat, Robin’s locket is released from his neck and smashes against the ceiling. The key flies from its enclosure and lands in the lock to Marian’s chastity belt. While attempting to sneak up on Robin, the Sheriff impales himself on Robin's sword, but Latrine rushes in and says she will give him a magic pill to survive if he agrees to marry her. He begrudgingly agrees and Latrine administers the pill, pulls out the sword and makes off with her new mate. Robin carries Marian to bed, but before he can unlock her belt, Broomhilde interrupts and insists that they marry first. Outside, Rabbi Tuckman performs the wedding ceremony. As he attempts to pronounce the couple man and wife an objection is raised by King Richard, who has just returned from the crusades. Taking his crown back from Prince John, the king punishes his brother by proclaiming that all toilets in the kingdom will be called "johns" and sentencing him to the Tower of London. The king then returns all Loxley properties to Robin, who is named ruler of Sherwood and knighted. After kissing Marian passionately, the king allows the wedding to conclude. Before leaving on his honeymoon, Robin appoints Ahchoo as the new Sheriff of Rottingham. Back at Loxley Hall later that night, Robin finally turns the key to Marian’s chastity belt. When the lock won't open, Robin calls out for a locksmith.