A gentle song begins as Melanie, Willow, Scarlet and Aya are shown lying all besides one another sitting in a circle. "The One and only has come and there can only be one! And at Last I am Here!" Willow, Scarlet and Aya fade away as Melanie is shown sitting up as she suddenly was on the Destiny Islands beach. Melanie turns to look behind her at the sound of her name. Riku held his hand out with a smile. Sora and Kairi stood beside him with smiles on their faces. "Why can't I even breathe? Standing in the wreckage." Melanie reaches for Riku's hand before the ground caves out beneath them. "The rain, a lullaby and so I close my... eyes." Sora is shown with Donald and Goofy fighting off Heartless together before light flashes and Roxas, Axel and Xion are shown standing together as they faced away from Aya who turns to look back at them before they fade away and she laughs as she talks with Roxas, Pence, Olette and Hayner. "Within this world if you wish to live another day! You must disguise as a flower that will captivate!" Light flashes and Willow's flower pod is shown before Willow is shown floating inside before Ventus is shown sitting on his chair as Aqua, Scarlet and Terra floated like ghosts before they vanish into black smoke. Scarlet is shown reaching for Terra before she fades away. Riku is shown standing in his regular form before he's shown in the Organization outfit facing away from himself. "You, I want to believe! But I cannot believe!" Disney characters are shown as Melanie, Scarlet, Willow and Aya are shown flashing across the area like a ghost. "I'm powerless! I'm meaningless! Like every scar! But as I cry, tears fill inside right through my heart!" Kairi is shown standing on the beach alone as she stares out into the ocean waiting for her friends to return. "Through it all, I can hear someone whispering, 'come near'! All that I miss, it's infinite!" Xehanort is shown at the top of a rock with his organization members around him before Terranort is shown with a smile on his face and Scarlet is shown floating behind him with a sad look on her face. "And so I see! Tomorrow's come with a new sun waiting for me! The One and only has come! And there can only be one! And at Last... I am here!" Queen Minnie, Daisy, and King Mickey are shown standing together. "There is a part of me that wants to forgive you!" Riku and Sora are shown fighting off Xemnas. "But I will not forget – I can't understand...yet." Riku is shown reaching for Melanie with Sora whose shape changes into Ventus and Roxas slowly as Willow and Aya are shown over Melanie before Melanie's eyes open and she grabs Riku's hand. "Within this world if I were to live another day! I must learn this song and quickly learn to play along!" Light Flashes and Kairi is shown reaching for Sora as the two were being separated by a rift. "If I want to believe! I just need to believe!" King Mickey is fighting off enemies with Riku in order to get to Melanie. "Freedom's a lie – Even so I must cross that line!" Light Flashes and Aya is shown as a child laughing with Lea and Isa before light flashes and Axel is shown standing in front of Melanie before he looks over his shoulder to see Saïx and the rest of the first Organization staring at them. "I'll scream it loud – Barren, I shout 'I'll make it mine'!" Light Flashes as Willow, Ventus, Aqua, Scarlet and Terra are shown laughing together before Willow and Ventus fall back asleep just as Terra turns into Terranort, Scarlet gets bound in chains and Aqua is absorbed in darkness. "And so I turn away from the truth that's in my way!" Light Flashes and Willow, Scarlet, Melanie and Aya are shown standing together with their backs to one another as they stand in a circle. "Defy the gods, despite the odds! I'll find that light! Something so pure – I'll search the world into the night!" Ventus, Terra and Aqua appear in front of Willow and Scarlet before Roxas, Axel, and Xion are shown standing in front of Aya. "The one and only has come and there can only be one! And at last..." The two groups fade away as Willow, Scarlet and Aya are shown turning into three floating hearts that enter Melanie and she closes her eyes as she held her hand against her chest before she opens them to find Riku, Kairi, Donald, Goofy and Sora smiling at her while Riku had his hand outstretched to her. "I am here!" Melanie reaches towards Riku to take his hand before light flashes and the title is shown.
Ventus comes to on one of the highways. He looks around. He thought about what Xehanort said. He tried to remember more. He grabs his head.
"What am I? What has the master been keeping from me all this time?" Ventus asks and he notices the Land of Departure world.
[Meanwhile]
Terra spots Ventus heading towards the Land of Departure world. Terra was about to go after him when Xehanort contacted him.
"Master Terra. Find me... We must speak at once." Xehanort's voice explains.
"Master Xehanort!" Terra states and takes off to meet Xehanort. He arrived at the Keyblade Graveyard.
"Master Xehanort, you wished to see me?" Terra asks.
"There is no time to lose. I have terrible news. Ventus has stumbled upon the secrets of his origins. Vanitas has kidnapped Scarlet's body." Xehanort explains.
"What?" Terra asks surprised, "I... I just saw Ven, he passed right in front of me. What happened?"
"Ventus is on his way home. If you could have seen the fury in his eyes. Especially after Vanitas said he was going after Willow next. I'm certain he's capable of anything." Xehanort continues, "I fear the boy may attempt to force the truth out of Eraqus in order to protect Willow. Master Terra, you must hurry back and see to your friend's safety!"
"Of course." Terra replies. Terra flies away and Scarlet appears out of a dark corridor after he's gone.
"We're almost there." Xehanort explains.
"He'll make a better knight of darkness." Scarlet explains.
[Land of Departure]
Willow's body is shown laying in the spot that Eraqus placed her so she could rest. Outside, Ventus is shown returning. Eraqus looks at Willow's body as she has a slight reaction to her heart being so close to her. Eraqus heads outside and meets with Ventus.
"Ventus, you're alone? I thought that Aqua would – well, what matters is that you're home. You don't belong outside this world yet." Master Eraqus says, "You need to stay here where you can learn—" Eraqus gently places his hand on Ventus's shoulders.
"In your prison?" Ventus asks and Eraqus gasps.
"What?" Eraqus asks, gently letting go as Ventus slightly shoves his hands from his shoulders.
"That's your excuse... for keeping me imprisoned here, isn't it?" Ventus asks. Ventus steps a few feet back as he looks up at Eraqus.
"What did you hear?" Eraqus asks. Ventus took a fighting stance as he'd be ready to summon his Keyblade.
"That I'm supposed to be some weapon! Some kind of χ-BLADE!" Ventus exclaims.
"I knew it. Xehanort – he could never let it go." Eraqus says and places his hand on his cheek. He remembers to when he got the scar on his cheek.
[Flashback]
Eraqus steps towards Xehanort as Juniper was not that far behind him. This was before Juniper left and vanished.
"Wait, Xehanort! There is a reason the precepts bar us from such knowledge. Why do you see the χ-BLADE? Would you blanket all the worlds in darkness, reduce them to nothing!?" Eraqus asks.
"But darkness did cover the world once, in legend." Xehanort replies, "We know so little about the Keyblade War - only that it was just the beginning. Amidst that crisis a precious light was found. It is a curious tale - and one worth exploring."
"Then the Princess of Dreams was given a purpose, to govern the light and darkness making sure neither one got to power. You'll throw off the balance of harmony." Juniper explains stepping over beside Eraqus.
"They say ruin brings about creation. So what, then, would another Keyblade War bring?" Xehanort wonders aloud, "When the darkness falls, will we be found worthy of the precious light the legend speaks of? I must have these answers. The χ-BLADE needs to be forged, and with it, the door to the Keyblade War unlocked!"
"Fool... you would risk an apocalypse out of sheer curiosity?" Eraqus asks.
"I won't allow it and neither will Eraqus, now while we live." Juniper explains summoning the Butterfly Dream Blade.
"But once again, you have it all wrong, you two." Xehanort states, "Darkness is a beginning, you see, not an end. At birth, every one of us emerges from darkness into a world of light, do we not?"
"Poetic excuses!" Eraqus replies.
"Give this up, Xehanort!" Juniper explains.
"If words won't dissuade you, only one thing will!" Eraqus explains, summoning his Keyblade as well. The two rush forward to attack. Eraqus jumps in front of Juniper and takes the hits.
"That power! Has the darkness taken you, Xehanort?!" Eraqus asks.
"Not your concern." Xehanort states. Juniper fires off a powerful light attack and Xehanort escapes.
[Present]
"I failed. I had the chance to stop him and couldn't do it. But I will not fail again." Eraqus states, summoning his keyblade.
'Master no!' Willow's voice says as she floats in front of Ventus like a ghost.
"Willow! Get out of him!" Eraqus orders.
"Master! What are you..." Ventus asks, confused.
"The χ-BLADE has no place in this or any world. Xehanort has made his purpose clear... and I am left with no choice. Forgive me!" Eraqus yells, "Get out of him while you have the chance, Willow, that is an order." Willow stares with wide eyes as she floats in front of Ventus. She looks at Ventus then back at Eraqus. Willow's eyes rim with tears. His eyes widened as she stretched her arms out in front of Ventus in a protective stance.
'I'm sorry, Master Eraqus, but I am not your pupil. I've never been able to summon my keyblade which makes me unfit to be your student. I will not allow you to hurt Ventus!' Willow's voice states, as the tears stream down her cheeks.
"Then neither one of you shall exist no more!" Master Eraqus says and Ventus's eyes widen.
"Willow, no!" Ventus yells as Willow changes into the light shield.
"VEN!" Terra's voice yells moments before impact.
"What?" Master Eraqus exclaims. The dust clears to reveal Terra standing protectively in front of Ventus and the ghost form of Willow.
"Master, have you gone mad?!" Terra asks.
"Terra! I command you – step aside!" Master Eraqus orders.
"No!" Terra fires back angrily.
"You will not heed your Master?" Master Eraqus asks.
"I won't!" Terra yells.
"Why do all my attempts to reach you fail?" Master Eraqus asks, "If you don't have it in your heart to obey... then you will have to share Ventus and Willow's fate."
"Willow?" Terra asks, confused. He didn't know that the light shield was Willow.
"Willow's heart is occupying mine! She's been with me and Aqua on our entire journey. She tried to be there for you too, Terra, but couldn't reach you. Because Scarlet's protecting you!" Ventus explains.
"Scarlet's not protecting me. I haven't felt her my entire journey, just heard her call out to me a few times. Willow, you have to return to your body." Terra asks.
'I refuse!' Willow's voice says, 'Ventus hasn't done anything wrong!'' Master Eraqus rushes forward to attack.
"Enough, Terra! He's right!" Ventus yells.
"Quiet!" Terra yells out. Deflecting blow after blow from Eraqus with his keyblade. He was good at defending himself against Eraqus's moves. Eraqus did train him after all.
"Terra..." Ventus pleads. Master Eraqus fires an attack at them and they both get thrown back. Terra stands up and he looks at Ventus. He helps him stand. Eraqus was summoning another attack. Terra activates the darkness and Willow's eyes widen.
'Terra...' Willow's voice says.
"You may be my master but I will not... let you hurt my friends!" Terra yells out.
"Has the darkness taken you, Terra?!" Eraqus asks, angrily. Terra summons a portal. Terra throws Ventus into the portal and as Willow's body rests inside.
"Wait, Terra!" Ventus yells out as the portal closes. Terra fights off Master Eraqus. It was a long and brutal battle. Scarlet didn't want to watch but she couldn't do anything. She was trying to protect Terra's true heart from all the darkness. It was using all her power. When the battle is finished, Terra gasps in shock.
"What have I done... Master... I just... wanted to keep Ven and Willow safe." Terra explains.
"No, you were right. I failed you, Terra. Perhaps I've no one to blame by myself for the darkness inside you. And now I've done worse - raised my Keyblade against you, Ventus and Willow. My own heart is darkness." Eraqus explains. He falls and as he does he begins to fade into light. Eraqus looks at Scarlet at the last minute and as Terra catches him, he and Scarlet become the protective light of Terra's heart.
"Master Eraqus!" Terra cries out. Two sets of footsteps approach and Xehanort looks down at Terra.
"What a sight. Why do you trouble yourself with remorse, Master Terra? The man was bent on doing harm to your friend, his own pupil! You accomplished your goal. Scarlet has awakened." Xehanort explains and Terra gasps and looks up. Scarlet approached as well. She stood staring at him but her beautiful blue eyes were a golden color.
"Scarlet!" Terra exclaims.
"You've done it, Terra." Scarlet explains, "I'm free."
"You know, at times, I find your progress quite striking. But you still fall short." Xehanort explains, "Let all that anger out, my boy. Give your heart over to darkness! Be the Knight of Darkness that Scarlet needs! There's too many lights ready to purify her true self again!"
"What do you mean?!" Terra asks summoning his keyblade.
"Still so blind. Then I will make you see. Come to the place where all Keyblade wielders leave their mark on fate - the Keyblade Graveyard! There Scarlet will take over as the true Princess of Dreams! The Princess of Dreams only exists in darkness! There you will watch your dear Ventus and Aqua meet their ends and then Scarlet will come back and snuff out the light here, and the last light within you will die!" Xehanort opens a portal and starts to destroy the world.
"You won't need a home anymore where you're going." Xehanort explains.
"What?! Xehanort?!" Terra asks in shock. Xehanort starts to go through a portal and Scarlet follows. Terra gasps as he realizes that Willow was in danger. Terra rushes inside and grabs Willow's body. He sends her through a portal to get her to safety.
"Willow... I'm sorry. I should have been filled with light so that you could guide me as well." Terra apologizes as he takes her to safety, "I won't let them hurt any of you. I'll free Scarlet from darkness."
[Meanwhile - Destiny Islands]
Ventus comes through the portal and tries to return but that's when Vanitas shows up. Willow gasps.
'Ven! Above you!' Willow warns.
"Going somewhere?" Vanitas asks.
"I'm through with you!" Ventus fires back. He starts to walk away.
"Well, I'm just getting started with you." Vanitas states, "You're strong enough now to fulfill your purpose. So what are you waiting for? Join with me right here and now. Become the χ-Blade."
"No, I won't do it." Ventus responds with his back still to Vanitas, "He told me the only way the χ-BLADE can be forged is if you and me fight. Well guess what? I'm not fighting."
"You used to be too broken to talk back." Vanitas states. Ventus screams in pain as Vanitas makes memories appear.
"Fine. Then I'll give you a reason to fight. After all, I already have your little princess. She's waiting at the Keyblade Graveyard." Vanitas lies.
'My... My body?' Willow asks in shock.
"Give her back!" Ventus yells. Vanitas laughs and he leaves to go get her. Ventus gives chase, heading to the Keyblade Graveyard. He intercepted Terra and attacked Terra separating him from Willow. Vanitas grabs Willow and looks at her.
"Hmm, so this is what the little light looks like. What do you see in her?" Vanitas mutters to himself and carries her to the Keyblade Graveyard. He held her out to Scarlet and Xehanort.
"Good. She'll bring all three of them here." Xehanort explains.
[Meanwhile]
After picking up Mickey on the highway between the worlds, Aqua takes Mickey to Master Yen Sid. It takes Mickey a while to awaken.
"Aqua, the stars bring me grave news. Master Eraqus's star has blinked out. I am afraid that means he has been struck down." Yen Sid announces to Aqua. Aqua gasps in surprise.
"The Master? But - Who is responsible?" Aqua demands to know. Yen Sid sighs, hesitant to tell her.
"Master Xehanort and Terra." Yen Sid announces. Aqua gasps in shock before slamming her hands down onto the table.
"NO! That's absurd! Terra would never!" Aqua yells.
"I hope with all my heart that you are right about your friend. There are some things even the stars cannot tell me." Yen Sid explains.
"Where is he? Where can I find Terra?" Aqua asks.
"Terra's heart is leading him to the ancient Keyblade Graveyard, where wielders of those weapons once waged war." Yen Sid explains.
"And... Willow's body?" Aqua asks.
"Also at the Keyblade Graveyard." Yen Sid confirms.
"Alright, I have to go after him... and see if it's true." Aqua states.
"Be on your guard." Yen Sid warns. Aqua nods and she quickly leaves.
'Terra, Ven, Willow... Please just be safe. I'll find a way to get you out of this.' Aqua's thoughts say.
[Keyblade Graveyard]
Terra arrives first and he summons his keyblade. He stares out at the entire area from where he was. He thought of all his friends, Master Eraqus and finally Scarlet.
"What I do, I do for friendship." Terra whispers as he knew he'd have to purify Scarlet's body of darkness and free her heart. He walks away to confront Scarlet, Vanitas and Xehanort.
[Later]
Ventus arrives at the same spot that Terra was at and had left about ten minutes before. He looks around in search of Vanitas. He was there to rescue Willow. He summons his keyblade, making a vow on the coming battle as well.
"Friends forever." Ventus explains. He also walks away to confront everyone.
[Later]
Finally, Aqua arrives. She looks over the area. She takes a deep breath. She summons her keyblade to make a vow over the coming battle. She looks down sadly before getting a determined look on her face.
"The five of us will always be one." Aqua declares. She walks after Ventus and Terra to confront the battle.