Nancy Drew and the Drew Crew prepared for the next phase of their investigation into the mysterious arson cases that had led to Bobby Nash's tragic death. The group sat around the dining table in their stylish Airbnb, their laptops and notes scattered around them as they strategized their next moves.

Suddenly, the silence was broken by the shrill ring of Nancy's phone. She glanced at the screen, seeing an unknown number. Frowning slightly, she answered, "Nancy Drew Investigations."

A distorted voice on the other end spoke urgently, "Meet me at the charred house in Hollywood Hills. Come alone."

Before Nancy could respond, the line went dead. She quickly relayed the message to the group.

Nick frowned. "It could be a trap, Nancy. Are you sure about this?"

Nancy nodded decisively. "I have to go. Whoever it is might have information we need. I'll take an Uber to the address. You all stay here and keep working on the case. I'll update you as soon as I can."

Bess looked worried but supportive. "Be careful, Nancy."

As Nancy stepped out into the cool night air and ordered an Uber, her mind raced with possibilities. The address led her to a charred and ruined house in Hollywood Hills. The house had once been a beautiful home, now reduced to blackened walls and ash.

Nancy cautiously approached the front door, which hung loosely on its hinges. Stepping inside, she was met by the smell of smoke and burnt wood. The eerie silence was interrupted by a figure emerging from the shadows.

"Are you Nancy Drew?" the man asked. He was tall, with a calm demeanor that contrasted sharply with the chaos around him.

"Yes, I am. And you are?" Nancy replied, keeping her voice steady.

"I'm Amir Casey," he introduced himself. "I'm a burn unit nurse."

Nancy raised an eyebrow. "You called me here. Why?"

Amir's expression was serious. "I needed to talk to someone who could help. I've been following the recent arson cases. I used to know Bobby Nash. He came to me a few weeks ago, asking for information about some burn victims we had treated."

Nancy's interest was piqued. "Do you know anything about this house? And do you have anything to do with what happened here?"

Amir shook his head. "No, I had nothing to do with this fire. But I know that the fires, including this one, are connected. Bobby was onto something big. He discovered a pattern in the locations of the fires and the victims."

Nancy asked, "What can you tell me about Bobby's death? Do you know if it was connected to his investigation?"

Amir sighed. "Bobby was digging into something dangerous. He found out that someone was deliberately setting these fires to force people out of their homes. The properties were then bought up by a shell company linked to Derek McAllister. Bobby thought he was close to proving it, but then he died."

Nancy's eyes narrowed. "Do you have any connection to Derek McAllister?"

Amir hesitated, then nodded slowly. "I treated someone who worked for McAllister. He came in with severe burns, but he was terrified to talk. From what I gathered, McAllister is using muscle to intimidate people and clear out properties. That patient hinted that McAllister was behind the arson, but he wouldn't give details."

Nancy's mind raced. "Do you have any evidence? Anything that can link McAllister to the fires and Bobby's death?"

Amir reached into his pocket and handed her a flash drive. "This contains medical records and notes Bobby left with me. It's not conclusive, but it might help you piece things together."

Nancy took the drive, her heart pounding with the possibilities. "Thank you, Amir. This could be the break we need."

As she prepared to leave, Amir grabbed her arm gently. "Be careful, Nancy. McAllister is dangerous. If he knows you're onto him, he'll come after you too."

Nancy nodded, her resolve hardening. "I'll be careful. Thank you, Amir."

She left the charred house and took an Uber back to the Airbnb. The Drew Crew was anxiously waiting for her return. She walked in and placed the flash drive on the table.

"This is what Amir gave me," she said. "It might have the evidence we need to connect McAllister to the fires and Bobby's death."

Ace quickly plugged the flash drive into his laptop and began going through the files. The group crowded around as he scrolled through medical records, notes, and Bobby's personal observations.

Nick pointed at the screen. "Look at this. Bobby identified a pattern in the locations of the fires. They all happened in areas where McAllister was trying to buy properties."

George added, "And here are notes from Bobby about a shell company linked to McAllister. It's clear he was using it to acquire the properties after the fires."

Bess looked up, worry etched on her face. "We need to get this to the authorities, but we have to be sure it's airtight."

Nancy nodded. "We'll keep digging. If we can find one more piece of solid evidence, we can take this to the police and bring McAllister down."

As the night wore on, the Drew Crew continued to piece together the evidence, determined to seek justice for Bobby Nash and stop McAllister's sinister plans.