Lois Duncan

Lois Duncan is an American novelist and author of teen mystery novels. She has penned more than fifty novels and is the recipient of the Margaret A. Edwards Award. Many of her works have been chosen as American Library Association "Best Books for Young Adults" and Jr. Literary Guild Selections, and they have won Young Readers Awards in 16 states and three foreign countries.

Lois Duncan is best known for her 1973 young adult suspense thriller I Know What You Did Last Summer, which was made into a feature film in 1997. Duncan has expressed distaste with the notion of her novel being realized as a teen slasher film, particularly in light of her own personal tragedy, the loss of her her daughter, Kaitlyn Arquette, who was murdered in Albuquerque, New Mexico in 1989. The case remains unsolved. Duncan wrote a non-fiction account of the tragedy in 1992 in the book Who Killed My Daughter?.