Alexander is a wolf with blue-black fur, darker across his back and lighter underneath. He is Luri's mate and the biological father of Akru and Sura. Discovering the infant Mowgli in the jungle, Alexander and Luri adopt the man-cub despite opposition from their pack. When Shere Khan first attacks, Alexander defends Mowgli, standing his ground to protect his family.

He later advocates for Mowgli's formal acceptance into the pack during the council meeting, securing support from Baloo and Bagheera. Years after, following pack leader Akela's retirement, Alexander assumes leadership after a mandated combat with the rival wolf Vermillion, though he dislikes the conflict. Declared leader under jungle law, Alexander does not consider the role permanent and expresses willingness to return leadership to Vermillion should he ever return.

As leader, Alexander teaches Mowgli fishing techniques but delegates hunting instruction to Bagheera, recognizing Mowgli's human limitations. During a forest fire, he dies defending his pack from Shere Khan, succumbing to his injuries in Mowgli's arms. His death leads Akela to resume temporary leadership before Luri eventually takes over.

Alexander's legacy influences Mowgli's development, particularly in episodes exploring Mowgli's memories of his adoptive father's teachings and his unresolved desire to confront Shere Khan.