故事紧接着上一季，金钱的紧缺和癌症的侵袭都不再是沃尔特（布莱恩·科兰斯顿 Bryan Cranston 饰）将要面对的难解问题了，家庭的濒临破碎才是让沃尔特感到心痛的真正原因所在。由于妻子斯凯勒（安娜·古恩 Anna Gunn 饰）坚定的离婚决心，沃尔特从家中搬出，搬入了新的居所，这也为他和大毒枭古斯（吉安卡洛·埃斯珀西多 Giancarlo Esposito 饰）之间的合作创造了有利的条件。 为了替死去的图可（雷蒙德·克鲁兹 Raymond Cruz 饰）报仇，两位冷面杀手找到了汉克（迪恩·诺里斯 Dean Norris 饰），激烈的交锋后，汉克身负重伤。面对着逐渐失控的一切，沃尔特感到了前所未有的危机，尤其是他的新搭档盖尔（大卫·科斯塔贝尔 David Costabile 饰），沃尔特明白，一旦盖尔掌握了他独创的制毒技术，自己将很快被古斯除掉。
In the series opener we meet Nancy Botwin, a recently widowed suburban soccer mom who's dealing pot to make ends meet; Nancy flips out when she discovers Josh, one of her competitors, is dealing to 10 year-olds at her youngest son's school, but she soon discovers a bigger skeleton in Josh's closet; Nancy is stunned when Quinn, her rival Celia's 15 year old daughter, asks her permission to have sex with her 15 year old son, Silas; Celia thinks her Nanny-Cam is the perfect solution to keep the kids celibate, but she ends up seeing much more than she bargained for.
