In ancient times, the world was ruled by gods and monsters, but it was the half-god Perseus
who defeated the monster known as kraken and saved the world.
His father Zeus offered him to rule by his side as a reward, but Perseus turned him down
because he preferred to live as a human.
Eventually Perseus' wife died, but this didn't make him change his mind.
He still lives as a simple fisherman and takes good care of his son Helius.
One evening, Zeus visits Perseus to bring some bad news: the gods are losing their powers
because humanity doesn't pray anymore.
This means they can't keep the demons inside the gates of Tartarus anymore and soon Cronus,
the colossal titan and father of all gods, may escape and bring calamity to the world.
Zeus wants Perseus to help them with this, but Perseus refuses because his priority is
his son and he doesn't think he has enough power to make a difference anyway.
After Zeus leaves, Perseus goes to bed and begins having nightmares about Cronus attacking
his village and almost killing his son.
Meanwhile Zeus meets with his brother Poseidon and his son Ares, who isn't happy to hear
Perseus isn't coming, considering him irresponsible.
They travel to Tartarus to repair the walls and there they come across Hades, who still
hates his brothers Zeus and Poseidon for banishing him into the underworld.
Because of this, Hades decides to betray his family and attacks by releasing fireballs
and monsters.
A fierce battle begins but since the gods are weak, they can't fight at full power and
Poseidon is heavily struck.
Zeus is distracted by his brother's loss and Ares takes the chance to knock out Zeus to
join Hares instead.
Then Ares steals Zeus' thunderbolt to become more powerful.
At that moment, a bunch of chimeras climbs out from the Underworld to attack humans all
over the world.
Perseus sees one land in his village and rushes back to retrieve his sword to protect his
home.
The villagers gather around the crater the beast left, but soon the chimera comes back
and causes everyone to run in fear.
A chase begins through the village as Perseus tries his best to fight the monster and keep
an eye out for his son.
Whenever the chimera breaths fire, Perseus uses whatever he has at hand as a shield,
and when he gets close enough he stabs any part of the beast he can reach.
He ends up being knocked to the ground, but when the chimera is about to kill Heleus,
Perseus puts himself together and gets the chimera's attention on himself, causing it
to get tangled in a bunch of chains.
The monster begins running away and drags Perseus with it, and once they're outside
the village, Perseus grabs the chains and tricks the creature into breathing fire, which
causes the chimera to burn itself.
Afterward, Perseus asks a healer to take care of his wounds and Helius to come with him
to the Mount of Idols, a place where people used to worship the gods but nowadays is in
ruins.
They find Zeus' statue and start praying, but the one to show up is Poseidon, who barely
managed to escape at the last second.
He tells Perseus about the betrayal and that Zeus has been captured, so Perseus must find
Poseidon's son Agenor, who is with Queen Andromeda, and together they shall look for the fallen
god Hephaestus, who has the key to defeating Cronus.
Then Poseidon asks Perseus to give his son his trident before he dies.
In the meantime, Zeus is chained up in order for Tartarus to absorb his powers and use
them to free Cronus.
Ares uses the moment to explain he hates his father because he's always had clear favoritism
for Perseus, who insulted the gods by preferring to live as a human.
Cronus has promised Ares and Hades immortality if they free him, but Zeus thinks it's all
a lie to get them on his side.
Back in the village, Perseus finally accepts he needs to fight so he says goodbye to Heleus,
who gifts his father a dagger he made himself.
Then Perseus calls for his black pegasus, who takes him high in the sky.
This allows him to find Queen Adromeda's armies, who are getting ready to fight near the entrance
to the underworld.
The archers attack Perseus when they see him fly by, but they quickly put their weapons
down when they realize this is the hero that defeated the kraken.
While everyone kneels to him, Perseus reunites with Andromeda and tells her everything, including
the fact they need to stop praying to Ares or they'll summon his presence.
Andromeda accepts to help and takes Perseus to see Agenor, who is in jail for being a
liar and a thief.
Perseus explains the situation and Agenor turns him down, not wanting anything to do
with the gods that abandoned him.
However Perseus points out this could get him freedom, so Agenor asks for a royal pardon,
gold, and a boat in exchange for his help.
Andromeda accepts to give it all to him for the sake of humanity.
Later on Agenor's new boat, Andromeda learns that Hephaestus was the one that made Poseidon's
trident, Hades' pitchfork, and Zeus' lightning bolt.
If they put those three together, they can form the Spear of Trium, the weapon the gods
used to defeat Cronus the first time.
Hephaestus lives on the island of Kail, which was never found, but Agenor swears he knows
how to get there.
Perseus accepts to free him from his chains and hands him the trident, which Agenor immediately
sticks in the boat to guide it to the island.
When they make it to Kail, they realize there are hidden traps everywhere.
Andromeda's guards want to pray to Ares for protection, and Perseus has to remind them
that Ares isn't on their side anymore.
The group tries to be careful, but Agenor still walks into a wire and gets captured
inside a trap.
While they discuss how to get him out, the trap is suddenly taken away by its ropes,
and Perseus tries going after it only to find a tree being thrown at him.
Perseus quickly dodges it and is shocked to discover a cyclops is behind all this.
Andromeda's team tries to help him, but a second cyclops shows up and begins killing
the soldiers.
Andromeda hides with her guard Korrina, who tries to pray to Ares and Andromeda has to
shut her up.
A cyclops is about to find them, but suddenly it hears a painful scream from its companion
and it rushes to check on it.
It turns out Perseus has managed to stab the cyclops following him, and with the help of
the soldiers, he activates one of the forest's traps to knock it out.
The second cyclops comes to attack and Perseus activates the trident to defend himself, this
causes a third cyclops to show up and stop its companions because the trident is the
symbol the group was sent by the gods.
Agenor is freed and the cyclopes kneel for Perseus in respect.
Meanwhile Ares takes advantage of Zeus being chained to start hitting him over and over.
Ares doesn't know his own limits, so Hades has to stop him before he ruins the plan.
Zeus begins aging at a great speed as the chains cover his arms in lava to absorb his
power.
Moments later, the group finally makes it to Hephaestus' lair.
The old god doesn't sound very sound of mind, but he recognizes Perseus and informs him
he can't help because he doesn't have godly power anymore since Zeus took it from him
when he banished him to the human realm.
Andromeda grabs Hephaestus' hand and begs for his help, which is enough to make him
change his mind because Andromeda reminds Hephaestus of his wife Aphrodite.
Hephaestus then reveals he was the one that designed Tartarus and included a secret passage
they could use.
They need to get to the heart of Tartarus, and for that they need to cross the labyrinth
that surrounds it.
The group leaves to reach a different building where Hephaestus has hidden the labyrinth
entrance, and he gives Agenor a map of the labyrinth just in case.
When they're about to make it to the door, suddenly Ares shows up.
He kills Andromeda's remaining soldiers and Perseus punches him for it, but he isn’t
strong enough to cause damage.
While Hephaestus opens the hidden door, the group attacks Ares, but he's too strong and
easily pushes them all away.
Korrina gets on her knees and reveals she was the one that prayed for him, but Ares
thanks her by killing her.
Seeing they're all about to be defeated, Hephaestus keeps the door open with his staff then goes
to confront Ares to buy the group some time.
While Ares takes his time killing Hephaestus, Perseus, Andromeda, and Agenor run inside
the labyrinth, and the door closes behind them.
The trio begins exploring the labyrinth using the map Hephaestus left them.
Perseus keeps hearing a voice calling his name and asking for his son, and Andromeda
sees a vision of Korrina that runs away from her.
After lots of twists and turns, Agenor decides the map is useless and that they should follow
his navigator instincts he got from his dad.
At that moment, the walls start moving and closing paths around them, so the trio runs
away before they get crushed.
They reach an inner area of the labyrinth with giant moving rings that cause them to
fall and get stuck between two walls.
The semi-gods use their strength to get Andromeda out, and Agenor quickly follows, but Perseus
falls again.
In a dark corridor, Perseus finds Heleus and has to remind himself he isn't real.
He goes looking for his friends only to be suddenly attacked by a minotaur, who tries
to stab him with its horns.
A fierce fight begins and after lots of struggle, Perseus manages to push the minotaur into
a wall to get its horns stuck.
Perseus then begins beating him up, and when the horns break, the minotaur tries to use
Heleus voice to ask for mercy, but Perseus kills it anyway.
Since the minotaur was the protector of the labyrinth, now that it's dead a clear path
opens for Perseus.
He reunites with his friends and together they finally enter the heart of Tartarus.
Meanwhile Zeus apologizes to Hades for banishing him into the underworld and confesses he forgives
Hades for capturing him now.
Hades starts changing his mind since he's always wanted the approval of his family,
but at that moment Ares shows up and attacks him to stop him from freeing Zeus.
After exchanging a few hits, Hades grabs Ares and makes them fall into the abyss while Cronus
finishes absorbing Zeus' power and finally starts waking up.
The trio arrives and Perseus uses Poseidon's trident to free Zeus while Ares makes his
way back up, ready to keep fighting.
Andromeda and Agenor try to stop him to no avail, but suddenly Ares falls when Hades
attacks him from behind with his pitchfork.
The trio runs away with Zeus as Ares takes the pitchfork from Hades and throws it at
Zeus, stabbing him in the back.
Zeus uses this as an opportunity and puts together the pitchfork and the trident to
make the group teleport out of Tartarus.
Furious, Ares stabs Hades, then he checks the area to discover Perseus dropped Heleus'
gift.
Minutes later, the group appears at Andromeda's camp, but Zeus doesn't have much time left.
He tells Perseus that Ares has his lightning bolt, so they need to steal it and make the
spear, which only Perseus can wield.
The group makes a plan: Agenor, Andromeda, and her army will hold Cronus back while Perseus
gets the bolt.
He prays to Ares and asks him to meet him at the temple, which he reaches by flying
on his pegasus.
The entrance to the underworld explodes and fireballs begin falling all over the area,
bringing all kinds of monsters with them.
The humans fight with all the weapons and strategies they can muster, but they won't
be able to hold on for much longer.
Suddenly Hades shows up at the battlefield to visit Zeus, holding his hand as he accepts
to forgive him and shares his last bit of power.
This makes Zeus look young gain and heals his wounds.
Then both gods join the fight, bringing down monsters as if they were flies.
Meanwhile Perseus arrives at the temple and discovers Ares has brought Heleus because
he wants him to watch his father be taken away like Ares had to watch his own.
A fierce fight begins between the brothers, but it's easy for Ares to overpower a semi-god.
When Ares is about to kill Perseus, Heleus' comes forward with his dad's sword, which
distracts Ares.
Perseus uses the chance to jump on his brother from behind and steal the lightning bolt,
which he then uses to finally kill Ares.
Now that he has the three weapons, Perseus puts them together to create the Spear of
Trium.
Meanwhile Cronus finishes awakening and appears on the battlefield, so Hades and Zeus concentrate
on attacking him.
Their power is weak and can't do much, thus Cronus ignores them to start destroying the
area instead, shooting lava all over the place.
Perseus arrives on his Pegasus, but he can't come closer to strike because of all the raining
lava.
Hades and Zeus put their powers together to land a good hit on Cronus and give the chance
Perseus to fly closer, this enrages Cronus and causes him to hit the land to send a powerful
wave toward the gods.
Zeus pushes Hades out of the way and puts up a force field, but he isn't strong enough
and gets hit back.
This distraction is enough for Perseus to dodge Cronus' last lava wave and flies directly
into his mouth to stick the spear directly inside his body.
The plan works and Cronus explodes until nothing but ash is left behind.
The army celebrates and Andromeda is glad to see Perseus flying back alive.
Afterward, Perseus reunites with Zeus, who mentions the era of gods is over and thanks
Perseus for his help.
Since Hades can't buy him any more time, Zeus dies in his son's arms.
Then Hades announces he's powerless now, so he'll have to start a new life.
Moments later, everyone at camp begins taking care of their wounds.
Agenor bonds with Heleus because he wants to be a good uncle, and Perseus approaches
Andromeda to kiss her.
When father and son get a moment alone, Heleus admits that after seeing war, being a fisherman
doesn't seem so bad.
However Perseus wants him to be ready for the future and decides to pass on his legendary
sword.