Conan stared out over the city from the roof of the Beika Hospital. How could this be happening? Approximately four hours ago, a strange girl, about the same age as Ran, had shown up at the Mouri Detective Agency, claiming to be his (well, Shinichi Kudo's) twin sister. Which was complete nonsense. How could he have not known about this? Ran had taken the girl and him (for no apparent reason) over to the hospital to check, since the hospital would probably have Shinichi's information. They were currently waiting for the results. He heard a door creek, and turned around. The strange girl was heading straight towards him. "I am Shinchi Kudo," she said, finally announcing her name. Then she looked at him straight in the eye. "Your twin sister." Conan's eyes widened. He didn't expect her to know who he was. But apparently, she did. "Let's go," she said, taking his hand gently. "Ran has already gone back. We're going to Professor Agasa." Conan, still slightly startled, went along with her, too dazed to argue.

Eventually, they arrived at Agasa's house. 'Shinchi' led him inside. The professor was sitting at a table, reading a thick book. He looked up.

"Hello, Shinchi-kun, Shinichi."

Conan stared at the professor. "H-how do you know who she is?"

Agasa laughed. "Of course I do," he said. "She's been stopping by every month after hearing about what happened to you. But of course, you never saw her. Your parents only recently granted permission for her to see you."

Conan looked at the professor, confused. "Permission?" Shinchi nodded slightly at them, then walked into another room, leaving Conan and Agasa to talk in peace together.

Shinchi stepped into the room. "I see you're doing well, Miyano."

Ai looked at the newcomer. "Yes," she answered coldly, still typing away on the computer.

Shinchi looked around for a moment, and stepped closer towards the young girl. "Long time no see," she said after a while.

Ai stopped typing. Then she stood up, about 1 meter shorter than the other girl. She slid forward, and they embraced in a silent hug. "I haven't seen you since you left the organization," Shinchi muttered.

"I had to," Ai said. "They would have killed me." The two females broke apart. Shinchi sat down in another chair. The two began to chat, smiling brightly(or as much as their characters allowed them to) and looking happy to be in the world.

Meanwhile, Conan was in quite a bit of shock. "I-I didn't know about a sister or anything," he stammered.

Agasa looked down sympathetically. "Of course, you didn't," he said. "You two were separated at birth. Your parent's didn't want an older female, so they got rid of her."
Conan looked up at him in surprise. "Got rid of?"

The professor nodded. "She was sent to China a week after you two were born. No one else knew but me. And, apparently, she was very eager to find you."

The boy was silent, taking in the news and slowly processing it in his brain.

Agasa looked at him for a while. "Never mind that," he said. "There's a reason why your parents gave her permission to see you. You three have to solve a case. Now."

"Three?" Conan asked.

Agasa faced him. "Yes, three. Come out now!" he called to the person behind the pole. A leg appeared, and after that, Hattori Heiji stepped out from behind it. "Yo!" Conan sighed. "You, huh?" Heiji nodded, smiling. "Well, then," he said. "Let's get started on this case!"