FX’s “American Crime Story: The People v. O.J. Simpson” has found its Gil Garcetti.

“Mad Men” alum Bruce Greenwood has signed onto the limited series to play the Los Angeles County district attorney who was a prosecutor in one of the most famous murder trials of the 20th century.

Based on Jeffrey Toobin’s “The Run of His Life: The People v. O.J. Simpson,” the drama is said to show the behind-the-scenes dealings and maneuvering on both sides of the court. It also stars Cuba Gooding Jr. as O.J. Simpson, John Travolta as defense attorney Robert Shapiro, David Schwimmer as defense attorney Robert Kardashian and Sarah Paulson as prosecutor Marcia Clark.

“American Crime Story: The People v. O.J. Simpson” is written by Scott Alexander and Larry Karaszewski. They are exec producing along with Ryan Murphy, Nina Jacobson, Brad Simpson and Brad Falchuk. Murphy is also directing the first episode. The series is produced by Fox 21 Television Studios and FX Productions.

Greenwood’s credits also include the films “Flight” and “Star Trek Into Darkness.” He is represented by Gersh and Binder & Associates.