Weekly Prompt Writing

Two days late, but here it is.

Brian shrugged on a lab-coat and grabbed a pair of latex gloves. "Alright, let's see what we've got." He swept over to the microscope, which was focused on a piece of cloth. After a few minutes of humming and muttering to himself, he straightened and took up a clipboard and pen.
"Was I right, Dr. Caldwell?" said the other person in the lab. "I don't know how we're going to break it to Mrs. Pearson that her son was poisoned."
"Please, Charlie," said Brian, putting up a hand. "You have twice my charisma, but none of my skill. The arsenic on the cloth does not imply that he was poisoned. But it does imply that the nurse was using poison in his vicinity."
"...Which would lead to the conclusion that the nurse poisoned him."
Brian stared into the microscope haughtily for a while before answering. "Yes. He was probably poisoned. Now go tell Mrs. Pearson."
Charlie paused in taking off his lab-coat to protest. "How come that's always my job?"
"As I said, you have twice my charisma," said Brian, putting down the clipboard. "She might faint again if I so much as walk into the room."