Haldo, there. Pazoink speaking.
I watched 'Ring 0: Birthday' last night, and it just gave me an idea. Here is said idea, in full 2 a.m. glory. It's a conversation Sadako's two sides have when she's in the well.
"Good Sadako speaking"
Evil Sadako speaking
She gripped the cold, rough stone as hard as she could, clinging on for dear life. Her hands felt like they were on fire, the pain was so terrible. Her fingers were slick with blood.
She reached up with one hand, hoping to feel the well-cover in the pitch black, but instead her hand came into contact with the side of the well. She grasped another stone and pulled herself up.
Suddenly, she felt a horrible, lancing pain and a snapping sensation. She let go instinctively, and plunged down again, into the water below.
Every time you fall down it's the same question: why?
"Why did you kill them?"
They wanted to hurt us, Sadako. I had to protect us.
"Why did father do this?"
Father? He is not our father.
"He said he was."
He lied. They all lied.
So many questions. You always ask questions! Stop asking questions! Climb and be free!
"My fingernails are all gone, now, Sadako. My head hurts. They're all gone. No one can hear us."
Excuses… so much superfluous thoughts. Let me be in control, Sadako. Please, I want to help. Let me climb. You must be tired. Rest and let me climb.
"Rest… no! If I let you control us, I might never be able to come back! I have to keep you calm."
I would never imprison you, Sadako. I care about you so much. I am the only one who cares. I always cared about you. Remember the sea? When we were little? I told you not to go in and I saved you.
"You care about me? What about everyone else?"
They never cared. Only I care.
Not again. Why what?
"Why did you kill him?"
I killed quite a few 'hims'. I am afraid you're going to have to be more specific.
"You know who I mean. Who we mean."
"Yes, Toyama. I loved him, Sadako."
"He loved me."
No! He never loved you! He only admired you power. Our power.
No human could ever love you, Sadako. Only what you have. They want you to cure their sickness, to heal their pain. To prolong their lives at the cost of your own!
"Toyama would never! He loved me! He loved me!"
Lies! Pitiful lies!
"No… it isn't true…"
They would imprison you. Call you a fraud to your face and a miracle to your back. Remember our mother? As soon as they realised she wasn't of any use they attacked her like a pack of hounds!
"Stop it! Go away!"
I can't go away. We're the same, you and I.
"Not the same. Not the same!"
We're prisoners in this together. And I know about being imprisoned.
"Not the same! Not the same! You killed Toyama! You killed him"
We killed him! And they would have killed you and me both if I hadn't saved us.
You're talking to yourself here. We're in so far in blood that there is only one way out and that is up! This well is nothing to us when we are together! We can be free! I can be free! You wouldn't deny me freedom, would you?
You got to live your life and I was trapped in an attic, cold and dark. You became beautiful and I stayed as an ugly little child! Why is that fair?
"You were evil, Sadako. You are evil."
I am not evil! I am you and how can you be evil? I am your ears in the silence! Your strength in your sorrow! Your eyes in the dark of a covered well! Oh, let me climb, Sadako. You seem so tired today. Let me climb, and we can both taste freedom!
"I don't want you to climb. I want you to stay down here and rot. You killed them and I hate you! I don't want to be a part of you!"
Too late! You called me because you were tired and weak and now I'm here to stay!
"Then I will go. Be the eyes in the dark. Now you have no face to be in. I refuse to be with you any longer.
"Good! You will see! I will climb and I will be free! Hide all you want, but- Sadako?"
She shifted slightly and her eyes opened. A handsome face came into focus and smiled at her. Sadako smiled back. She saw with delight that at long last she was with Toyama once more.
"You were dreaming." He said. Sadako just looked at him, never wanting to be parted from him again. "You fainted. Do you remember?"
"You left me. Fine then. Now I am in control, and they had best be sorry for what they did to us."
Uh… hope you understood that. At the end, good Sadako gave up and died, leaving only her evil side in the well, and at that point her hate and anger only become stronger, although she hasn't got to the point where she has made the videotape. As for good Sadako, I'm not sure. She could be replaying a memory, or maybe she's been reunited with Toyama in spirit, or maybe something else has happened. Your choice.