After seeing everything Claire went through dealing with the uncertainty of a threat hanging over her head Alex decided that messing with Talana's peace of mind was all he could do. He checked to be sure none of the neighbors had any security cameras on their houses before running to a 24/7 convenience store far enough away that no one would look there for a potential perpetrator. He put his hood up and kept his back to all the cameras to be safe.
He didn't need much. Gloves, an envelope, a blank card, and a pen. He was sure to write the note left-handed as well since it was his non-dominant hand and would look different from any handwriting of his that might be on file.
It said very little. Writing out all he was feeling would take more cards than he could count. He wrote a single sentence. 'I know what you did.'