Really Nasty Bunch

I had to walk over to Nash quickly. "I found a suspect," I whispered. Nash turned to me with shock. 

"How did you do that?" he asked. I shrugged. 

"I have keen senses. I was talking to Sebastian yesterday about how frustrated the whole thing made me and the conversation put things in perspective. I am almost positive I know who did this." I stared at him. He was not going to believe me. I just knew it. 

"Okay, tell me. Who is it?" He looked around the perimeter to see all the faces. "I can't figure it out. Quickly tell me."

"Your four o'clock. Blonde shoulder length hair and mauve flowy dress." He inconspicuously glanced towards the direction and shook his head. "Listen to me," I said firmly. Nash closed his mouth, his lips forming a line. "She was there when we found Patrick, too. I noticed her staring at me but didn't think much of it then. When I came out now, I saw her smile." 

"Smile?" Nash asked, confused.