At the beginning of the game, a young boy named Link is awakened by a telepathic message from Princess,
who says that she is locked in the dungeon of nearby Hyrule castle. As the message closes, Link finds his uncle ready for battle, telling Link to remain in bed.
After his uncle leaves, however, Link ignores his uncle's command and follows him to the dungeons under Hyrule castle.
When he arrives, he finds his uncle mortally wounded.
Link's uncle tells him to rescue Princess from her prison, saying "Heroes is your ..." giving him his sword and shield and soon dies.
Link navigates the castle and rescues Heroes from her cell, and the two escape into a secret passage through the sewers that leads to a sanctuary.
Link is told by the priest in the sanctuary that agahnim, a wizard who has usurped the throne,
is planning to break a seal made hundreds of years ago by the Seven Sages.
The seal was placed to imprison a dark wizard named Ganon in the dark World,
a near-mirror of Hyrule which was once known as the sacred realm before Ganon invaded it, obtained the legendary triforce held there,
and used its power to turn the realm into a land of darkness.
Agahnim intends to break the seal by sending the descendants of the Seven Sages who made the seal into the dark World.
The only thing that can defeat Agahnim is the Master Sword, a sword that can only be wielded by the chosen hero and forged to combat evil.
To prove that he is worthy to wield it, Link needs three magic pendants, hidden in dungeons guarded by mythical defenders.
On his way to retrieve the first, he meets an elder, Sahasrahla, who becomes Link's mentor, offering hints and advice at key stages of the journey.
After retrieving the pendants, Link takes them to the resting place of the Master Sword.
As Link draws the sword from its pedestal, Heroes telepathically calls him to the Sanctuary, informing him that soldiers of Hyrule castle have arrived.
Link arrives at the Sanctuary moments after the soldiers have vacated, where he learns from the dying Sanctuary keeper that Heroes has been taken to Hyrule castle.
Link goes to rescue her but arrives too late; Agahnim sends Heroes to the Legend Heroes Zelda Combat Monsters.
Link then faces Agahnim in battle and defeats him, but Agahnim's last act is to send Link to the dark World as well.