These are their stories: Sam Waterston will leave ‘Law & Order’ later this month after 400 episodes

NEW YORK — Sam Waterston, who has played the spiky, no-nonsense district attorney on “Law & Order” since the mid-1990s, is stepping down from his legal perch. An actor doesn’t want to let himself get too comfortable.” Tony Goldwyn, who starred in “Scandal” and the 1990 film “Ghost,” has been cast as the new district attorney. McCoy and the prosecutors would take up the legal case once the New York City detectives were finished investigating a crime, representing, as the narrator says, “two separate yet equally important groups.” McCoy was a brilliant, hard-charging, angel of justice, prone to bouts of moral outrage and slicing right to the truth. That led to Waterston playing Nick Carraway in “The Great Gatsby” opposite Robert Redford, and the role of Tom Wingfield in a television production of Tennessee Williams’ “The Glass Menagerie,” starring Katharine Hepburn, for which he got his first Emmy nod.