Greta had been giving piano lessons out of her home for 25 years. She had seen it all. Kids who were being forced by their parents to learn the instrument. Adults with rock-star dreams who were told learning piano would help them better understand music and thrash harder on their guitars. Middle-aged people who always wanted to learn and, now that their children were grown, they were finally doing something for themselves.

But she had never met anyone like Philip.

He was 10 when he started taking lessons from Greta. His mother pushed him into learning music as a way to “focus him.” Greta assumed he struggled with something like ADHD, but as she grew to know the boy, she quickly saw that was not where he struggled.

Greta was pretty sure Philip was a serial killer.

At first, he just seemed to be different. Where other kids his age would react, Philip stayed quiet. If Greta made a pathetic joke that caused other kids to roll their eyes, Philip would look at her with fascination, as if he was looking inside her soul for the true meaning of her silly puns. His smile would never reach his eyes and he would stare just a little too long. Greta would have to nudge him to begin playing his piece. If she didn’t he would just continue to look at her.

One afternoon, when Philip was 16, he was late for his lesson. Greta was sure that day would be the one where he finally snapped. When he arrived, he was panting, as if he’d just run the four miles from his house. When Greta opened the door for him, he wouldn’t stop apologizing, even when she said it was fine. He began to pace and his right hand grabbed at his jeans, fingers digging into the fabric. Greta tried every soothing word she knew, but the young man continued to have a panicked fit about being late. She had to touch his elbow gently to remind him that it was time to begin their lesson.

Philip sat at the piano and placed his books on the music stand. He took at a few deep breaths before opening his Hanon Schaum finger exercise book. It was as if he channeled all of his anxiety and anger at being late into the repeating patterns designed for dexterity that every kid hates. She had never heard him play so evenly. He didn’t miss a note.

After he left, Greta sent a text to his mom.

“Just checking in if everything is okay. Philip was late today and really worked up. Told him it was okay. But he played beautifully!”

Philip’s mom didn’t respond until well after midnight. Greta heard her phone ping as it sat charging on her nightstand near her bed. She was still awake reading, and as she glanced and saw who had sent the message, she put her book down and read the response.

“I’m sorry I dropped him off late. My fault. Work issues. Thanks.”

“No problem!” Greta sent, making sure to add a smiley face emoji.

A week later at Philip’s next lesson, he arrived with a giant smile, but there were droplets of sweat along his forehead and stains under his arms. Greta thought to herself again that it seemed like he ran to her house.

“Miss Greta, I’ve had the best day,” Philip rambled as he walked in. He was panting again.

“Philip,” Greta said with a chuckle. “Breathe! You sound out of breath.”

Philip laughed a little too hard and sat on the piano bench, spreading his books out.

“So I met a girl,” he began as he opened the exercise book and began playing. “Her name is Christina.”

Greta watched him carefully as he played perfectly while describing his new crush. He prattled on about how she was new to his school and how pretty she was. She was in his homeroom and he was sure she felt the same because of a look she gave him.

Greta was overwhelmed. She feared Christina may be his first victim.