The show - based on John Buntin's book L.A. Noir: The Struggle for the Soul of America's Most Seductive City - reunites former Walking Dead showrunner Frank Darabont with a number of the show's former cast members.
"This series is an intense, exciting drama that takes viewers back to a truly fascinating time in the history of Los Angeles," TNT president and programming chief Michael Wright said in a statement.
"Frank Darabont, Michael De Luca and Elliott Webb have delivered an outstanding opening episode that evokes the time and place in stunning detail. Together with a pitch-perfect ensemble cast and top-notch production crew, they have woven an engrossing tale of heroism in the face of greed and corruption.
"We're very excited to be working with such talented storytellers in bringing this project to life."
[[L] Jon Bernthal in 'The Walking Dead'; [R] Neal McDonough in 'Justified']
LA Noir tells the tale of the LAPD's attempts to bring down mobster Mickey Cohen. Jon Bernthal, who played Shane in The Walking Dead, stars as Los Angeles police officer Joe Teague.
Neal McDonough (Desperate Housewives, Justified) plays police chief William Parker, and Milo Ventimiglia (Heroes) will portray a former marine-turned-lawyer named Ned Stax, a man who becomes a 'fixer' for the mob.
The cast also includes Jeffrey DeMunn (The Walking Dead), Jeremy Strong (Lincoln) and Alexa Davalos (Clash of the Titans).
Simon Pegg will appear in the pilot as Hecky Nash, a stand-up comedian who has ties to the Los Angeles criminal underworld.