I'll Spell It Out

Zoe woke this morning to the sun shining in her window. She jumped out of bed with a jubilant feeling. She ended a tumultuous relationship with her boyfriend the night before and finally felt free. As she entered her apartment from a run, someone grabbed her around the neck. The attacker held a knife to her throat and dragged her to her bedroom. The terror Zoe felt at this moment paralyzed her. She felt tremendous pain and gasped. Blood drained down her back...

When officer Brooks saw in horror what was left on her back, he realized this killer was like no other...
Would this be the case of his career or the one that ended it?