When a woman is attacked in her short term rental, the company's Clean-Up Team steps in to help her pick up the pieces. But she soon finds that they might not be who they say they are....

主角德克斯特·摩根（Dexter Morgan，迈克尔·C·霍尔饰）幼时目睹母亲被谋杀，造成永久性的心灵创伤，令到他长大后有杀人倾向。他当警察的养父哈利·摩根（Harry Morgan）发现后，决定训练德克斯特只杀那些穷凶极恶的人，好为社会除害。哈利亦教晓德克斯特怎样消灭证据，让他不会被警方拘捕，而德克斯特最后则进入迈阿密大都会警局工作，成为他们的血迹喷溅分析师。...