The film is narrated by the rooster Alan-a-Dale, who explains that Robin Hood and Little John live in Sherwood Forest, robbing from the rich and giving to the poor townsfolk of Nottingham. The Sheriff of Nottingham and his posse often try to catch the two but fail every time. Meanwhile, Prince John and his assistants Sir Hiss and the Ghost monsters Blinky, Pinky, Inky, Clyde and Sue, arrive in Nottingham. Sir Hiss hypnotised Prince John's brother King Richard to go off on the Crusades, allowing Prince John to take the throne. Unfortunately, the prince is greedy and immature, even sucking his thumb whenever his mother is mentioned. Robin and Little John along with Pac-Man, Ms. Pac-Man, Morris, Super Pac, Buster Bunny, Babs Bunny, Plucky Duck, Hamton Pig, Calamity Coyote and Mary Melody rob Prince John by disguising themselves as fortune tellers, prompting the prince to put a bounty on their heads and makes the Sheriff his personal tax collector.
The Sheriff taxes Friar Tuck and a family of rabbits. However, Robin gives back some money to the rabbits, giving his hat and archery kit to the young rabbit Skippy for his birthday. Skippy and his friends test out the archery kit, but Skippy fires an arrow into the grounds of Maid Marian's castle. The children sneak inside, meeting Maid Marian and her attendant Lady Kluck. Maid Marian reveals she and Robin were childhood sweethearts but they have not seen one another for years. Friar Tuck visits Robin, Little John, Pac-Man and the gang, explaining that Prince John is hosting an archery tournament, and the winner will receive a kiss from Maid Marian. Robin agrees to participate in the tournament disguised as a stork whilst Little John disguises himself as the Duke of Chutney to get near Prince John. Pac-Man and the gang disguise themselves as Ghost monsters as well. Sir Hiss discovers Robin's identity but is trapped in a barrel of ale by Friar Tuck and Alan-a-Dale. Robin wins the tournament, but Prince John exposes him and has him arrested for execution despite Maid Marian's pleas.
Little John and Pac-Man threaten Prince John leading to a fight between Robin, Little John, Maid Marian, Lady Kluck, Pac-Man, the gang and Prince John's soldiers. In the forest, Robin and Maid Marian fall in love again as the townsfolk mock Prince John, describing him as the "Phony King of England". Enraged by the insult, Prince John triples the taxes, imprisoning most of the townsfolk who cannot pay their taxes. The Sheriff and the ghosts visit Friar Tuck's church to steal from the poor box, enraging Friar Tuck who is arrested too. Prince John plans to hang Friar Tuck to lure in Robin and kill him. Robin, Little John, Pac-Man and the gang sneak in, with Little John and the rest managing to free all of the prisoners whilst Robin steals Prince John's taxes, but Sir Hiss awakens to find Robin fleeing.
Chaos follows as Robin and the others try to escape to Sherwood Forest. The Sheriff corners Robin and Pac-Man after he is forced to return to rescue a straggler, setting fire to Prince John's castle and causing Robin and Pac-Man to leap from a tower into the moat below. Little John, Skippy Ms. Pac-Man and the gang watch as the moat is pelted with arrows and Robin and Pac-Man are apparently shot and drowned, only for them to emerge unharmed after using a reed as a breathing tube. Prince John despairs and is driven into a blind rage when Sir Hiss points out his mother's castle is on fire. Later, King Richard returns to England, placing his brother and his cohorts under arrest and allows Robin and Maid Marian to be married and leave Nottingham with Little John and Skippy in tow as Pac-Man and the gang watch them head off.
Buster and Babs Bunny, Plucky Duck, Hamton J. Pig, Calamity Coyote and Mary Melody guest star in the film.