Edie Falco as Leslie Abramson
The four-time Emmy winner (for The Sopranos and Nurse Jackie) is donning quite the wig to take on the role of Erik and Lyle's criminal defense attorney. During the infamous trial, she came under investigation by the state bar after invoking the Fifth Amendment when asked by the judge if she had Erik's psychiatrist delete and rewrite passages of his notes.
Miles Gaston Villanueva as Lyle Menendez
The older of the two brothers will be played by the relative newcomer.
For the first time in 20 years, Lyle spoke out about killing his parents in ABC's 2017 special Truth and Lies: The Menendez Brothers – American Sons, American Murderers. "It's shocking to think...that I could have been involved in taking anyone's life—and my parents' life...it seems unimaginable because it seems so far removed from who I am," Lyle said in a phone interview from prison. "But I found that my own childhood prepared me surprisingly well for the chaos of prison life."
Gus Halper as Erik Menendez
Another relative newcomer, Halper plays the younger brother, who was 18 when the murders were committed.
Carlos Gomez as José Menendez
Recently seen on Madam Secretary, Gomez takes on the role of Erik and Lyle's father, who was accused by the boys of sexually and psychologically abusing them throughout their childhood, leading to their decision to kill him in 1989.
Lolita Davidovich as Kitty Menendez
After stints on Shades of Blue and True Detective, Davidovich plays Erik and Lyle's mother, Kitty, who was most recently played by Courtney Love in Lifetime's movie about the murders.
Sam Jaeger as Detective Les Zoeller
After causing us to cry for years on Parenthood, Jaeger plays the Beverly Hills Police Department detective who was assigned to the investigation into the murders.
Josh Charles as Dr. Jerome Oziel
The Good Wife fan-favorite plays the pivotal role of Erik and Lyle's therapist, who heard the boys confess to the murders and became a key witness. Dr. Oziel later surrendered his license after being accused by a state panel of breaking confidentiality rules and having sex with female patients. Dr. Oziel denied the allegations, did not admit to any wrongdoing, and agreed to surrender his license because he no longer lived in the state of California and had not practiced in years, his attorney explained at the time.
Sterling Beaumon as Glenn Stevens
The role of Lyle's friend at Princeton, who was later called to testify during the trial, will be played by The Killing star, who also played Young Ben on Lost.
Anthony Edwards as Judge Stanley Weisberg
The ER vet plays the judge who presided over both trials.
Heather Graham as Judalon Smyth
Smyth was Dr. Oziel's ex-mistress who became a key witness after she told authorities she overheard the brothers confess to the killings, and also had audio recordings of her conversations with the psychologist. She will be played by The Hangover star.