Played by Nicholas Turturro: Originally assigned to the detective's squad as a temporary fill-in after Sipowicz was shot two years ago, Martinez demonstrated great enthusiasm for the job and willingness to learn, and quickly earned his detective's gold shield. His tenure on the job hasn't always been fun - he witnessed the OD death of his junkie brother, and watched his idol John Kelly get driven off the force. James is neither the brightest nor the most charismatic detective in the 15th squad, but he makes up for his occasional lack of savvy with a lot of heart and hard work. He recently transferred out of the squad after receiving a promotion to sergeant.
Nick would go on to appear in a few more Lee films, as well as "Mac," which brother John starred in and also directed. Nick moved out to Hollywood and began auditioning for TV parts, doing guest spots on "L.A. Law" and "Law & Order" before being cast as rookie detective James Martinez on "NYPD Blue."
Since Martinez was created solely as a foil for David Caruso's Det. Kelly, the writers seemed at a loss for what to do with the character once Caruso quit after the first season. Nick lingered in the background for the better part of five years (taking a lengthy break during season five to star in an NBC movie about Sammy "The Bull" Gravanao) before leaving the show early in season seven -- a decision that served both him and the show well. Though most of his film and TV work has been in drama (including an excellent indie flick called "Federal Hill"), since leaving "Blue," Nick's been focusing on comedy, first appearing in a WB sitcom pilot that didn't get picked up, and recently playing a New York chef in a pilot that failed to make CBS' fall schedule.
Nick has a daughter, Erica, from his marriage to Jami Biunno. In addition to his brother, his cousin Aida acts (she's Janice on "The Sopranos"), his brother Ralph is a musician, and his mother Katherine is an amateur jazz singer, with whom he once did a duet on "Late Night with Conan O'Brien."