Murder. In Hawaii's beautiful Hanauma Bay. The suspects: two young main-landers on their honeymoon. Maryann Acker, a pretty young Mormon woman, is eighteen. William, just out of prison, is twenty-eight. The crime is robbery, ending in a killing.
In 1982 Linda Spalding, a main-lander herself, living in Hawaii, is chosen as a juror for Maryann's trial there. Surprisingly, the chief witness against Maryann is William, accusing her of shooting their victim. Spalding has doubts, but on the last day of the trial she is abruptly dismissed from the jury, and Maryann is found guilty.
Who named the Knife is the story of how, eighteen years later, Spalding stumbles over the journal she kept during the trial and, reading it carefully, wonders if she was right to those doubts. She tracks down Maryann, who is still incarcerated, starts a correspondence, and begins to uncover much more than the answer to the question of Maryann's guilt or innocence. There's the bold new friendship frustrated by monitored visits, hard-to-make calls, and the dehumanising results of years in prison. But as her understanding of the forces that drove Maryann's actions grows, Spalding finds herself compelled to examine her own past as well as Maryann's.