When Richard the Lionheart, the King of England, is taken captive by Leopold of Austria while returning from the Crusades, his brother John takes power and proceeds to oppress the Saxon commoners. Prince John raises their taxes, supposedly to raise Richard's ransom, but in reality to secure his own position on the throne.
One man stands in his way, the Saxon Robin, Earl of Locksley. He acquires a loyal follower when he saves Much from being arrested by Sir Guy of Gisbourne for poaching one of the king's deer. Robin goes alone to see Prince John at Gisbourne's castle and announces to John's assembled supporters and a contemptuous Maid Marian that he will do all in his power to oppose John and restore Richard to his rightful place. He then escapes, in spite of the efforts of John's men.
His lands and title now forfeit, Robin takes refuge in Sherwood Forest with his friend Will Scarlet. There they meet and recruit Little John. Other men join their growing band. Later, Robin provokes Friar Tuck into a swordfight, but then persuades the friar into joining him to provide spiritual guidance to the outlaws. Soon, Prince John and his Norman cronies find themselves harassed beyond all bearing.
One day, Robin and his men capture a large party of Normans transporting the collected taxes through Sherwood. Among Robin's "guests" are Gisbourne, the cowardly Sheriff of Nottingham and Maid Marian. Robin and his men "liberate" the tax money, swearing to a man to use it towards King Richard's ransom. At first, Marian is disdainful of Robin and his "band of cut-throats", but becomes convinced of his good intentions. Robin tells the humiliated Gisbourne and Sheriff that they can thank Marian for their good fortune; in deference to her, he spares their lives and lets them go.
Prince John then comes up with a cunning scheme to capture Robin. He announces an archery tournament, with the grand prize a golden arrow to be presented by Maid Marian, knowing that Robin will be unable to resist the challenge. All goes as planned; Robin identifies himself by winning the competition and is taken prisoner. Gisbourne sentences him to be hanged. However, Marian warns Robin's men, and they manage to rescue him on his way to the gallows. Later in the dark of night, Robin sneaks into the enemy castle to thank her. Marian and Robin declare their love for each other.
Meanwhile, King Richard returns to England disguised as a monk, but is recognized at an inn by the Bishop of the Black Canons after he overhears one of Richard's men call him "sire". The traitorous bishop hurries to inform Prince John. Upon receiving the news, John and Gisbourne plot to dispose of Richard quietly before he can raise an army. Dickon Malbete, a disgraced former knight, is sent to assassinate him in return for the restoration of his rank and Robin's estate. Marian overhears them and writes a note warning Robin, but Gisbourne finds it and has her arrested and condemned to death for treason. Marian's nurse Bess informs her boyfriend Much, who intercepts and kills Dickon after a desperate struggle.
Richard and his escort travel to Sherwood Forest to find Robin. When Richard is certain of Robin's allegiance, he reveals his identity. News then reaches them when Much informs the Robin and Richard that John intends to have himself crowned king by the Bishop of the Black Canons in Nottingham the next day.
Knowing that the castle is too strong to take by force, Robin decides to use guile, visiting the bishop and "persuading" him to include Robin and his men in his entourage. Through this ruse, they gain entry to the castle and interrupt John's coronation. A melee breaks out, during which Robin and Gisbourne engage in a prolonged swordfight. Gisbourne is finally slain, and Robin rescues Marian from her cell.
Richard is restored to the throne; he exiles his brother, pardons the outlaws, returns Robin's earldom and orders him to marry Lady Marian.