Aquaman

Atlanna was forced to return to Atlantis because she had a duty as princess to fulfill an arranged marriage she had fled from. Before leaving, she entrusted her son to Nuidis Vulko, her loyal advisor, to train and protect him. This departure was necessary to maintain the political stability of Atlantis and avoid complications with her intended husband.

Earlier scenes show Atlanna's conflicted expression as she cradles baby Arthur, hinting at the painful choice to come.

The Atlanteans reject Arthur because he is a half-breed, born from a human father and Atlantean mother. Their society views pure Atlantean lineage as superior, making Arthur an outcast despite being the firstborn son of Queen Atlanna. This discrimination drives Arthur to abandon Atlantis and live among humans.

Vulko's training sessions show Arthur facing hostility from other Atlantean warriors from a young age.

David Kane seeks revenge because his father, Jessie Kane, died during Arthur's rescue of a Russian nuclear submarine. When Jessie and his pirates attacked the sub, Arthur intervened and saved the sailors. Jessie sacrificed himself to save David, but David witnessed his father dying and was left stranded in the ocean, fueling his hatred toward Arthur.

During the submarine rescue, David's desperate cry for his father establishes the personal tragedy that fuels his future vendetta.

Atlanna was not actually executed. Orm told Arthur this lie to hurt him. In truth, Atlanna was sentenced to the屿 Trench, a deadly underwater realm meant to be a death sentence. However, she survived and ended up in an uncharted sea where she was trapped but alive. Arthur discovers her alive during his quest for the trident.

Orm's revelation about the execution is delivered with subtle hesitation, hinting at deception.

The Trident of Atlan is a legendary weapon belonging to the first king of Atlantis. Possessing it grants the holder absolute authority over the seas and proves the rightful claim to the Atlantean throne. Arthur must obtain this trident to challenge Orm's rule and unite the seven underwater kingdoms against the looming war with the surface world.

Vulko mentions early that only a true king can wield Atlan's trident, establishing its importance to Arthur's destiny.

Orm, as the newly crowned King of Atlantis, views the surface world as a threat to the ocean's ecosystem and inhabitants. He believes humanity's pollution and exploitation of the seas justify war. Additionally, he sees conquering the surface as a way to unite all ocean kingdoms under his rule and prove Atlantis's superiority.

Orm's hatred for surface dwellers is established through his dialogue with advisors and his manipulation of David Kane.

Arthur chooses to spare Orm because he embodies the mercy and hope that his mother taught him. Rather than killing his half-brother in their final battle, Arthur shows compassion, believing redemption is possible. This act of mercy ultimately leads Orm to acknowledge their brotherhood and accept his defeat.

Arthur's journey is guided by Atlanna's lessons about hope and compassion, which contrast with Orm's ruthless ambition.

The mid-credits scene shows David Kane being rescued from drowning by Dr. Stephen Shin, a scientist obsessed with finding Atlantis. After David recovers, the two form an alliance driven by their shared hatred of Arthur. This sets up Black Manta's future role as a primary antagonist in potential sequels.

Dr. Shin is introduced earlier as an obsessed researcher who has been trying to locate Atlantis through dangerous expeditions.

Mera helps Arthur because she believes he is the rightful heir to the Atlantean throne as the firstborn son of Queen Atlanna. Despite her initial reluctance due to political pressures, she chooses to support Arthur because she knows Orm's war would bring destruction to both the surface and underwater worlds. Her loyalty to Atlantis and her sense of justice drive her decision.

Mera's early scenes show her disagreement with Orm's aggressive policies and her respect for Atlanna's legacy.

Aquaman can communicate with sea creatures due to his unique Atlantean heritage. As the son of Atlanna (an Atlantean princess) and Thomas Curry (a human), Arthur possesses special abilities that allow him to command and converse with marine life. This ability is an innate power that manifests from his mixed bloodline.

As a baby, Arthur is shown surrounded by sea creatures in his crib, demonstrating this ability from birth.

Arthur challenges Orm to a duel in a ring of lava to claim his birthright as the true heir to the Atlantean throne. When confronted by Orm in his cell, Arthur refuses to accept a life in exile and instead invokes the ancient Atlantean tradition of single combat to determine who deserves to rule. This challenge forces Orm to accept the duel under his own laws.

Vulko mentions earlier that only a challenge can force Orm to face Arthur in formal combat.

Arthur proves himself worthy by facing Karathen, the ancient mythical serpent that guards the trident. He must demonstrate courage, honor, and the ability to unite rather than conquer. By showing mercy to Orm instead of killing him and by commanding the loyalty of marine creatures, Arthur proves he wields the trident not for power but for protection.

The Oracle in the Sahara hints that worthiness requires the heart of a true king, not just the strength of a warrior.