On April 21, 2016, McNamara died in her sleep in the family's Los Angeles, California home. Her death was attributed to a combination of a previously undiagnosed heart condition and complications from prescribed medication (Adderall, Xanax and Fentanyl). The season 3 finale of The Goldbergs was dedicated to her memory. On August 1, 2016, Oswalt announced that he had been working to complete McNamara's non-fiction book on The Golden State Killer, which was left unfinished at the time of her death. In September 2017, Oswalt announced that the book, titled I'll Be Gone In The Dark, was scheduled for release on February 27, 2018 and was subsequently available for preorders.