Tuah [P. Ramlee], Jebat [Ahmad Mahmud], Kasturi [Nordin Ahmad], Lekir [S. Shamsudin], and Lekiu [Aziz Sattar] prove their bravery as teenagers by fending off pirates at sea. As adults, they study under Tok Guru Adi at Mount Ledang, where Melor [Datin Saadiah], a native girl, shares a quiet affection with him. After completing their studies, Tuah and his friends return to the Malacca Sultanate, and Tuah promises to wait for Melor if she seeks him out in Malacca.
In Malacca, the group saves Bendahara Dato' Tun Perak from an angry mob while he is on his way to meet Sultan Mansur Shah. Impressed by their bravery, the Sultan appoints Tuah and his companions as warriors, sparking jealousy among dignitaries like Tun Ali.
Soon after, the Sultan travels to Majapahit to marry Raden Mas Ayu, accompanied by Tuah and his companions. During a ceremony, Tuah demonstrates his skill by defeating the warrior Taming Sari and discovering that his opponent's strength lay in his magical keris. After Taming Sari's death, Tuah is awarded the keris, enhancing his power.
Later, Sultan Mansur Shah expresses his desire to marry Tun Teja [Zaiton], who is engaged to Megat Panji Alam. Tuah undertakes a secret mission to Pahang to bring Tun Teja to Malacca. Meanwhile, Melor arrives in Malacca searching for Tuah but encounters Tun Ali and Pateh Karma Wijaya. She tricks them into thinking she is a palace handmaiden to escape.
In Pahang, Tuah's deception leads Tun Teja to break off her engagement. On the return journey, Tuah reveals that his mission was to deliver Tun Teja to the Sultan. Though heartbroken, Tun Teja accepts her fate.
Back in Malacca, Tuah wrestles with loyalty to the Sultan and his love for Melor, who has become a palace handmaiden. On the persuasion of Dang Rani (under Tun Ali and Pateh Karma Wijaya’s orders), Tuah agrees to meet Melor. Their meeting is interrupted by the Sultan, who accuses Tuah of treason for consorting with a palace handmaiden and orders his execution.
Tuah’s sacred keris, the Taming Sari, is given to Jebat, who succeeds Tuah as the realm's lead warrior. Jebat, however, sees Tuah's punishment as unjust and vows revenge. Melor, seeking justice for Tuah, attempts to assassinate Pateh Karma Wijaya with a kerambit during a performance but is killed by a guard.
Jebat rampages through the Sultan's palace, forcing the Sultan to flee to the Bendahara's residence. Ashamed, the Sultan laments Tuah as the only warrior who could defeat Jebat. Tun Perak reveals that he secretly spared Tuah by hiding him in a prison cell, and the Sultan pardons him and summons him back.
Tuah asks for the Taming Sari keris to face Jebat, but the keris is with Jebat. Undeterred, Tuah confronts Jebat at the palace. Jebat argues that his actions were born of loyalty to their friendship, but Tuah insists on fighting. Unable to harm Jebat because of the keris's magic, Jebat ultimately offers to exchange kerises. Tuah kills Jebat with Jebat's own weapon, and Jebat dies in his arms.
With Jebat's death, Tuah is named Laksamana. The city cheers the victory, yet Tuah mourns Melor and Jebat, left to question whether unwavering loyalty to the Sultan justified the rebellion against injustice.
