Emergency doctor Emma Steele is, as always, terribly busy: she spends all her free time at work, saving the lives of patients - but what about her own life? After the divorce, Emma is kept company in the evenings by a bottle of red wine, her career growth is stuck, and her daughter, suffering from bipolar disorder, openly hates her mother. An unexpected series of terrible events - a stream of patients diagnosed with an overdose who cannot be treated with an antidote, the death of a mentor who miraculously escaped death friend - shakes Emma to the core and forces her to search for answers. She's incredibly smart and very observant, but will she be able to find the criminal before he gets to her?