Madmartigan was the son of a noble Daikini family of Galladoorn. He was given impeccable schooling, so that someday would ascend to administrative duties of the kingdom.
However he was far too restless and reckless and truant as a child. He would escape his lessons in the palace to visit Galladoorn's eclectic bazaars and became friends with a group of Eastern horsemen who taught him horseback riding and archery. At age ten, he was able to save his friends from bloodthirsty Pohas by slaying some. The famed swordsman Roniro noticed his raw talent and took the boy as an apprentice and taught the lost art of sushin, but died shortly after Madmartigan reached knighthood. Madmartigan befriended Airk Thaughbaer and never spent time with his fellow knights, preferring the company of caravan drivers.
He was at odds with minister Jarenth who was jealous of him.
When he fell in love with a princess Carissima of Cashmere and forced to choose between breaking the knight's code or his own heart. With Jarenth's orchestrations, she was convinced that Madmartigan had been cheating on her, the princess accused Madmartigan for revealing court secrets to her. Thus Madmartigan lost all honor along with the armor and stature of knighthood. He then spent much time in taverns and other haunts while Queen Bavmorda began to expand her borders, crushing all opposition. The knights of Galladoorn took to arms to repulse her at the Land's End, and Airk gave him one last chance to regain his honor. Madmartigan lost this opportunity by deserting Airk at Land's End.
As a punishment Madmartigan was led to the crow's cage at the Daikini Crossroads where he was left to die of thirst. He was freed by Willow Ufgood, who was seeking someone to watch over Daikini baby Elora Danan. Madmartigan took the infant to one of his many women acquaintances but the baby was kidnapped by thieving Brownies before Madmartigan got too far.
Willow retrieved Elora, and found Madmartigan at a roadside tavern, while dressing up as "Hilda" to hide the fact that he and a wench were cheating on her brutish husband, Llug. As Llug discovered his wife's indiscretion, Nockmaar soldiers appeared seeking Elora. Both Madmartigan and Willow narrowly escaped with Elora as Madmartigan took out the soldiers.
Seeing that both he and Willow had the same route, he saw him safely to the fishing village near the island where Fin Raziel was captive, but shortly after Nockmaar soldiers caught up to him. Although he did not give the location away, they rode to the fishing village where Willow and Raziel were taken prisoners by Sorsha and all were led to General Kael's camp. Rool and Franjean who followed Willow, freed them from the camp, but in the process, Madmartigan became smitten with a fairy spell, the Dust of Broken Heart that drew him to sleeping Sorsha. The confusion allowed him and Willow time to escape on a sleighing shield.
They ended up in a snow village to which Madmartigan arrived in the form of a rolling snowball. However the Nockmaar soldiers were after them. They hid in a basement where Airk and other soldiers were also hidden. As Sorsha searched the hut, Madmartigan took her captive at the knife's point. Airk denied to help them to Tir Asleen but as they left on horse, Airk and the Galladoorn knights stopped Bavmorda's soldiers to go after them.
The team fled to Tir Asleen but Sorsha questioned whether Madmartigan meant the words of love, and while riding in the canyon maze, she escaped them. Madmartigan and Willow arrived to Tir Asleen expecting an army to defeat Bavmorda. All they found instead was a cursed castle infested with trolls.
Madmartigan equipped himself with the armor of a knight from the castle's armory, and organized a singlehanded defense from Bavmorda's hordes, impressing Sorsha who abandoned her allegiance to her mother and fought by his side. Despite the arrival of reinforcements from the surviving knights of Galladoorn, the Nockmaar soldiers were able to steal away with Elora Danan.
Willow Ufgood brought the battle back to Nockmaar. While he, Sorsha and Fin Raziel infiltrated Bavmorda's tower, Madmartigan and Airk lead the knights in an attack on Nockmaar. With a clever ruse that hid their forces in covered trenches, they were able to make their way past the castle walls. Airk fell in battle, but Madmartigan took up his sword and defeated the Nockmaar commander, General Kael.
Willow and Fin Raziel were successful in destroying Bavmorda, and her reign of darkness came to an end. Raziel lifted the curse on Tir Asleen, and Madmartigan became a knight in service of the city as protector. However when the Cataclysm erupted, wiping Tir Asleen off the face of the world, and all those who inhabited it vanished.