Amalthea Lank is the estranged mother of Maura Isles in the Rizzoli and Isles book series. As revealed, she also leads a family of serial killers responsible for murdering pregnant women and selling their kids after cutting them out the moment the mothers die. When her daughter and Isles’ twin sister Anna Leoni is murdered, Amalthea’s crimes are traced, leading to her arrest and her son, Samuel’s death, born from the marriage to her cousin Elijah, who died of natural causes after assisting Amalthea for years. She’s the main killer in Body Double, but she appears again in I Know A Secret when she’s aged and dying.