This is how our Heroes arrived in Atlantica and how they defeat Ursula in Ryan's Quest.
Our Heroes arrived in Atlantica in Mermaid form and they saw Ariel coming
Ariel: Come on, Sabastion!
Sebastian: Ariel, wait! Slow down, don't leave me behind!
They saw our Heroes Flounder and Sebastian look scared
Ariel: Oh, Sebastian. Don't worry, they don't look like them. Right, Flounder?
Flounder: I don't know, there's something weird about them.
Ryan: What do you mean?
Ariel: You do seem... A little different. Where are you from?
Ryan: We are from a place far away and we are not used to these waters. [chuckles nervously]
Ariel: Oh, I see. In that Case... Sebastian can show you how to swim around here.
Sebastian: Ariel, King Triton would not like this!
Ariel: Oh, don't worry.
Sabastion: Easy for you to say... Okay, it’s time you learn how to swim properly. Practice swimming with Flounder. Try to tag him. All right. Begin
Evil Ryan: Ok.
They are follow Flounder and they did it
Sebastian: Good Job. Now, let's move onto Self-defense.
They saw the Heartless
Sebastion: Classes over! Good luck!
They are fighting and they defeated them
Ariel: Those creatures chased us here.
Sebastian: Oh, no! Those monsters might be heading for the palace, too!
Ariel: We’d better head back right away!
Flounder: But, wh-what if we run into more on our way back?
Ariel: I’m sorry, but we need your help. Please come to the palace with us. The trident markers on the walls point the way there. We won’t get lost as long as we follow them. Okay, let’s get going.
They went to King Triton's Palace and he blast the Heartless
Triton: That was too close. As long as I have my trident, I will not tolerate those creatures inside this palace.
Triton: Oh, Ariel! When will you listen? It's dangerous out there!
She felt Guilty
Triton: Strange creatures lurk outside.
Sebastian (clearing his throat): Behold. You swim before the ruler of the seas: His Majesty, King Triton.
Triton: And who are they?
Ariel: They helped us fight off those creatures.
Triton: They don’t look familiar.
Ryan: We’re from an ocean very far away.
Crash: Yeah. We came to find the Keyhole.
Triton: The what?
Ariel: What’s that?
Crash: Oh! Well, it’s a—
Triton: There’s no such thing! Certainly not here!
Ariel: But, Daddy...
Triton: Ariel, not another word! You are not to leave the palace. Is that clear?
They left and Triton look sad
Triton: Perhaps I’m being too strict... I’m just concerned for her safety.
He watch them left
Sebastian: Of course, Your Majesty. But I must admit, now I’m quite curious about this Keyhole.
Triton: That need not concern you, Sebastian. Have you anything to report?
Sebastian: Just as you suspected, Your Majesty, they seem to be coming from Ursula’s grotto.
Triton: I knew it. That sea witch is up to no good again.
He look angry
Triton: I see exile from the palace has taught her nothing.
Sebastian: Yes, she poses serious danger.
Triton: And I told you to keep Ariel away from such danger, did I not?
Sebastian: Your Majesty, please, I, uh...
Ariel: Come to my grotto. I want to show you something.
She pointed over there
Ariel: There it is. See?
They went to her Grotto
Ariel: Look at all the wonderful things Flounder and I’ve collected. I think it’s all from the outside world.
They look at all of her Collection
Ariel: Someday, I’m going to see what’s out there. I want to see other worlds. Does that sound strange?
Ryan: No. Not at all. I used to feel the same way.
Ariel: Used to?
Ryan: I mean...I still do.
Ariel: Hey, why don’t we try looking for that Keyhole that you were after.
Ryan: But you're Father said-
Ariel: Oh, he treats me like a little girl. He never wants to let me do anything. He just... He just doesn’t understand.
Sebastian heard everything
They left the Grotto and they didn't know that they been watched
Ursula: Those impudent fools will never find the Keyhole.
She make the Image of Ariel floats up
Ursula: But the girl could prove useful. And I’ve got the Heartless on my side.
Her Tentacles is moving
Ursula: Triton, my old friend... Your day is coming.
They went to the Sunken Ship and they found a Crystal Triton
Ariel: Hm. Its shape reminds me of something...
They return to the Grotto and put it here
Triton: Ariel, you’ve disobeyed me again!
Triton: I told you not to leave the palace!
He saw the Crystal and he's gonna destroy it
Ariel: Daddy, no!
Sonata: Don't do it!
He destroy the Triton Crystal
Ariel: How could you...
Triton: Young man, you’re not from another ocean. You’re from another world. Aren’t you?
Triton: Then you must be the key bearer.
Ryan: How did you know?
Triton: You may fool Ariel, but you can’t fool me. You don’t know your dorsal fin from your tail.
Triton: As the key bearer, you must already know... One must not meddle in the affairs of other worlds.
Ryan: Of course I know that, but...
Triton: You have violated this principle. The key bearer shatters peace and brings ruin.
Matau: Aw, Master Ryan's not like that.
Triton: I thank you for saving my daughter. But there is no room in my ocean for you or your key!
Ariel is crying
Flotsam: My, my, the poor child suffers such deep sorrow.
Jetsam: What a pity. If only there were something we could do...
Flotsam: Wait. Maybe she can be of some help.
Jetsam: Yes. Maybe she can be of some help to you.
Ariel: Who’re you talking about?
Flotsam: Oh, she would surely help you.
Jetsam: She’d make all your dreams come true.
Flotsam & Jetsam: Ursula can help...
Ursula has appeared
Ursula: You called, my dear?
Ariel: You’re Ursula? I was just wondering if—
Ursula: It’s all right. Helping others is what I live for. Let me guess. You wish to see other worlds. That shouldn’t be too hard. After all, your new friends came from another world.
Ursula swim to her
Ursula: But they had special help—that mysterious key.
Ariel look at the floor
Ursula: Now, now. Cheer up, sweetie. You have something special, too.
Ariel listen to her
Ursula: Now listen carefully. I think the Keyhole they seek is somewhere in the palace.
They went to the Palace
Ursula: Now, my dear, if you can take me there without your daddy knowing...
Ariel is gonna give the Triton to her
Ursula: I can help you get to these other worlds you long for.
Ursula: The trident is mine at last! And I couldn’t have done it without your help, my dear.
Ariel look after his Father
Ariel: Ursula, no! I didn’t want this!
Ursula: Why not? Aren’t you tired of following your dear daddy’s orders?
Ursula: Oh, yes. We had a deal, didn’t we? Time for a little journey—to the dark world of the Heartless!
Flotsam: We cannot find the Keyhole.
Jetsam: The Keyhole is not here.
She saw our heroes coming
Ursula: Why, we have company. I’m afraid you’re a little late, handsome!
Triton: The trident... We must get it back.
Ryan: Come on, let’s go!
They went off and Ariel stop them
Ariel: Wait, I’m going with you! My father is hurt and it’s all my fault. I have to stop Ursula!
Sebastian: That’s right. I’m right behind you, Ariel.
Triton: Ursula draws power from her cauldron. To defeat Ursula, you must strike her cauldron with magic.
Crash: Got it!
They went off and they found her
Crash: Come out! You can’t run!
Sebastian: Your time has come!
She look at them angry and it scare Crash and Sebastian, they are fighting them and they defeated Flotsam and Jetsam
Ursula: You'll pay for this!
Ariel: Let’s go. We must get the trident back.
They are going after her and they found her
Ursula: You pathetic fools! I rule the seas now!
She swim up and she began to grow
Ursula: The sea and all its spoils bow to my power!
They are gonna fight her and they defeated her
Ariel: Daddy, I'm so sorry.
Ryan: Please, don't be mad at her.
Ariel: Daddy, I’m so sorry.
Ryan: Please don’t be angry with her.
Triton: It’s my fault. You followed Ursula because... I wouldn’t let you follow your heart. And when you found that crystal, I lost my temper and destroyed it.
Sonata: Oh, yeah, the crystal! Why did you destroy it?
Triton: The crystal held the power to reveal the Keyhole. The Keyhole is dangerous. I had to keep you away from it at any cost.
Triton: Key bearer, I have one more request: Seal the Keyhole. My trident also holds the power to reveal the Keyhole. Will you do it?
Ryan: Of course. That’s what we had in mind from the start.
Ariel: Where is the Keyhole, Daddy?
Triton: You should know better than anyone. It’s in your grotto.
Crash: Really... Ryan, let’s go.
They are back in Ariel Grotto and the Triton restore the Crystal and it show the Keyhole
Ariel: Tell me, Ryan. Your world, what’s it like?
Ryan: Oh, about that... Sorry for lying to you.
Ariel: It’s okay. Besides, if you can travel to other worlds, maybe I can, too.
She swim up
Ariel: So many places I want to see... I know I’ll get there someday. I’ll find a way somehow. I’m sure of it.
Sebastian: Well, if you find it, do me a favor and leave me out of it.