"Law & Order" is a long-running and influential police procedural and legal drama television series created by Dick Wolf. It premiered in 1990 and ran for 20 seasons until 2010, with the series being revived for a 21st season in 2022. The show is set in New York City and is known for its two-part approach; the first half of each episode typically follows police detectives as they investigate a crime, and the second half follows the legal proceedings related to the crime, usually prosecuted by the Manhattan District Attorney's office. Given the show's extensive run, the cast changed numerous times. However, here are some of the main characters who had a significant impact on the series and their roles: **Police Officers:** 1. **Detective Lennie Briscoe (played by Jerry Orbach):** A wise-cracking veteran homicide detective with a troubled personal life, Briscoe was known for his dry wit and deep compassion. He appeared from Season 3 to Season 14. 2. **Detective Mike Logan (played by Chris Noth):** A hotheaded young detective with strong instincts, Logan was one of the original main characters. He appeared in the first five seasons and later returned in various spin-offs. 3. **Detective Rey Curtis (played by Benjamin Bratt):** A devout Catholic and family man, Curtis was the junior detective paired with Briscoe for a significant part of the series (Season 6 to Season 9). 4. **Detective Robert Goren (played by Vincent D'Onofrio):** Though primarily a character on the spin-off "Law & Order: Criminal Intent," Goren was a brilliant, intense, and sometimes unconventional detective with an ability to understand and get into the minds of suspects. **Legal Professionals:** 1. **Executive Assistant District Attorney Jack McCoy (played by Sam Waterston):** Known for his moral passion and tendency to push the boundaries of the law, McCoy was a central character from Season 5 to Season 20 and became the District Attorney in the latter seasons. 2. **District Attorney Adam Schiff (played by Steven Hill):** The wise and sometimes politically savvy DA who often guided his ADAs through the political landscape of the legal system, Schiff appeared from Season 1 to Season 10. 3. **Assistant District Attorney Claire Kincaid (played by Jill Hennessy):** A young and idealistic ADA who worked closely with Jack McCoy, Kincaid appeared in Seasons 4 to 6. 4. **Assistant District Attorney Serena Southerlyn (played by Elisabeth Röhm):** An ADA whose stance on various issues sometimes brought her to conflict with her bosses, Southerlyn was featured from Season 11 to Season 15. 5. **Executive Assistant District Attorney Michael Cutter (played by Linus Roache):** A determined and complex ADA who worked under Jack McCoy when he became DA, Cutter was a main character during the last few seasons of the series. Keep in mind that this is a small selection from a larger ensemble cast that featured many rich characters throughout the series' long tenure. The characters’ effectiveness in their roles, along with the shows' procedural aspects, helped "Law & Order" leave a lasting mark on the television landscape, becoming one of TV's most enduring franchises, which includes several spin-offs, TV movies, and international versions.