A stark and moving meditation on grief, love, and survivorship, Unimaginable is a mother's account of her only son's struggle and ultimate succumbing to his addiction, and her enduring capacity to love and heal. On the morning of January 28, 2018, Liz Pettit lived her worst nightmare: when she went to wake her only son Zach, she discovered that he had died in the night, an accidental overdose of fentanyl-laced opioids. His struggles with social anxiety and substance use disorders ended an incredibly bright twenty-three years of life. Through journals, poetry, and raw recollections of the events of his passing, Liz shares her memories of Zach, revealing a young man who, like many suffering from this disease, had so much to offer the world. As she tells their stories - one ended by tragedy and another bolstered by a drive toward survival - she illuminates a path forward for those navigating this grief-filled journey. Sadly, Liz's story is not unique. As some parents are forced to reckon with the trial and sad aftermath of the disease of addiction, Unimaginable serves as a sympathetic guide and proof that a parent's love always endures.