The Blue Bloods Season 13 finale, titled "Forgive Us Our Trespasses," ended with a family dinner gathering. Erin, initially planning to announce her candidacy for Manhattan DA, changes her mind due to recent events. Danny reunites with his former partner, Jackie, to investigate a case involving Dr. Leonard Walker. They discover Walker suffers from dissociative identity disorder and has been killing victims. Frank disagrees with Mayor Chase's plan to remove homeless individuals, and they eventually come to a resolution with the help of Archbishop Kearns. The season ends with the question of Walker's whereabouts.