The message arrived at midnight.
I found it on my phone, a text from an unknown number. No name. No identification. Just a single line of text that made my blood run cold.
Your blood is the key to everything, Leon. But your blood is also the prison. The equation isn't a weapon. It's a cage. And you're the only one who can unlock it.
I stared at the message for a long moment, feeling the weight of its words. My blood. The key. The prison. The equation. Everything was connected.
"Leon." Elena's voice came from behind me. "What is it?"
I handed her the phone. She read the message, her face going pale.
"This is bad," she said. "Very bad."
"Who sent it?"
"I don't know. But I think I know what it means."
"What?"
She was silent for a long moment. Then she said, "Your blood isn't just th
