"Law & Order" started as a failed pilot in 1988 for CBS that took the television airwaves by storm 2 years later when the show debuted on NBC. Starring then unknown actors, no one would have thought that this little show would last into the next century.

Dick Wolf created the series as a two-tiered format, where the first half would follow the detectives of the 27th Precinct trying to solve a murder, and in the second half the Assistant District Attorneys would try to convict the guilty. Little did Wolf know that he had phenomenon at his fingertips.

The series hit ratings highs in the mid 1990s and created numerous spin-offs after. The first, "Law & Order: Special Victims Unit", detailed major sex crimes and became a ratings juggernaut. Soon following, "Law & Order: Criminal Intent" would air, following the Major Case Squad. However, while some spin-offs bloomed, others faltered. "Law & Order: Trial by Jury" came in 2005, and was canceled soon after. This series dealt completely with the trial side of cases and featured Jerry Orbach's last performances before his untimely death. Currently, the United Kingdom has taken a stab at the "Law & Order" franchise creating "Law & Order: UK", the first adaption of a "Law & Order" series in another English-speaking country.

The series has now entered a remarkable 20th year and has launched the careers of Jerry Orbach, Jesse L. Martin, Benjamin Bratt, Chris Noth, Angie Harmon, Sam Waterston, and many others. While the many series have hit some ratings struggles of late, the show still continues to be a fan favorite on the airwaves and syndication. Whether watching in the early afternoons on TNT or watching new episodes Fridays on NBC, "Law & Order" is one of the few constants left in an ever-changing America.

"Law & Order" has been known for the revolving cast door. Below is a complete list of cast members of the flagship series:

Law
George Dzundza as Sgt. Max Greevey (Season 1)

Paul Sorvino as Sgt. Phil Cerreta (Episodes 23-52)
Jerry Orbach as Det. Lennie Briscoe (Episodes 53-325)
Dennis Farina as Det. Joe Fontana (Seasons 15-16)
Chris Noth as Det. Mike Logan (Seasons 1-5)
Benjamin Bratt as Det. Rey Curtis (Seasons 6-9)
Jesse L. Martin as Det. Ed Green (Episodes 206-407)
Milena Govich as Det. Nina Cassidy (Season 17)
Jeremy Sisto as Det. Cyrus Lupo (Seasons 18-Present)
Anthony Anderson as Det. Kevin Bernard (Episodes 408-Present)
Michael Imperioli as Det. Nick Falco (Episodes 346-349)
Dann Florek as Capt. Don Cragen (Seasons 1-3)
S. Epatha Merkerson as Lt. Anita Van Buren (Seasons 4-Present)

Order
Michael Moriarty as E.A.D.A. Ben Stone (Seasons 1-4)
Linus Roache as E.A.D.A. Michael Cutter (Seasons 18-Present)
Richard Brooks as A.D.A. Paul Robinette (Seasons 1-3)
Jill Hennessy as A.D.A. Claire Kincaid (Seasons 4-6)
Carey Lowell as A.D.A. Jamie Ross (Seasons 7-8)
Angie Harmon as A.D.A. Abbie Carmichael (Seasons 9-11)
Elizabeth Rohm as A.D.A. Serena Southerlyn (Episodes 254-338)
Annie Parisse as A.D.A. Alexandra Borgia (Episodes 339-371)
Alana de la Garza as A.D.A. Connie Rubirosa (Seasons 17-Present)
Stephen Hill as D.A. Adam Schiff (Seasons 1-10)
Dianne Wiest as Interim D.A. Nora Lewin (Seasons 11-12)
Fred Dalton Thompas as D.A. Arthur Branch (Seasons 13-17)
Sam Waterston as (E.A.D.A. 5-17, D.A 18-Present) Jack McCoy (Seasons 5-Present)