The movie On the Basis of Sex is not just a legal drama—it’s a powerful story about justice, equality, and determination. Released in 2018, the film tells the story of Ruth Bader Ginsburg, one of America’s most iconic Supreme Court Justices. But what truly brings this story to life is the brilliant cast that portrayed real-life historical figures with heart and depth.
In this article, we take a deep dive into the cast of On the Basis of Sex, highlight their roles, and explore how their performances made the film so memorable.
Felicity Jones as Ruth Bader Ginsburg
At the heart of the movie is Felicity Jones, who plays Ruth Bader Ginsburg. Known for her role in The Theory of Everything and Rogue One, Jones delivers a passionate and respectful performance.
She captures Ruth’s intelligence, strength, and calm resolve. From courtroom scenes to quiet personal moments, Jones shows the emotional and intellectual depth that made RBG a legend. Her preparation included studying Ginsburg’s speeches, interviews, and even her posture and voice. The result is a powerful and authentic portrayal.
Armie Hammer as Martin Ginsburg
Armie Hammer plays Martin “Marty” Ginsburg, Ruth’s husband—a supportive, kind-hearted man who believes in his wife’s brilliance. This role was essential in showing the personal side of Ruth’s life. Hammer’s performance brings warmth and charm, reminding us that behind every great woman, there can be a great man who supports and uplifts.
Marty’s humorous and caring personality is portrayed with subtlety. Armie’s chemistry with Felicity Jones makes the relationship feel natural and inspiring.
Justin Theroux as Mel Wulf
Justin Theroux takes on the role of Mel Wulf, the director of the ACLU and a key figure in Ruth’s legal journey. His performance is energetic and thoughtful, showcasing the struggles and support systems involved in Ruth’s path to success.
Theroux brings a mix of skepticism and hope, embodying a character who helps Ruth bring her case to life while pushing her to prove her worth in a male-dominated legal world.
Kathy Bates as Dorothy Kenyon
The legendary Kathy Bates plays Dorothy Kenyon, a civil rights lawyer and activist who had inspired Ginsburg. Though her screen time is limited, Bates brings authority, experience, and a sense of continuity to the feminist movement.
Her presence in the film connects Ginsburg to the larger history of women’s rights, making her short scenes impactful and emotionally rich.
Sam Waterston as Erwin Griswold
Sam Waterston plays Erwin Griswold, the Dean of Harvard Law School and later Solicitor General of the United States. As a symbol of the old legal system, Griswold represents the barriers Ruth faced.
Waterston plays the role with a calm but stern demeanor, making the character a subtle but strong adversary. His performance highlights the generational and ideological gap Ruth had to bridge.
Cailee Spaeny as Jane Ginsburg
Cailee Spaeny plays Jane Ginsburg, Ruth’s daughter, who represents the new wave of feminism and youthful determination. Jane is sharp, confident, and supportive of her mother’s mission.
Spaeny’s performance shows how the next generation views change differently. She becomes Ruth’s inspiration and reminder of why fighting for equality matters.
Jack Reynor as Jim Bozarth
Jack Reynor plays Jim Bozarth, one of the lawyers opposing Ruth in court. His character is firm but not villainous. Reynor manages to show how the legal system itself is structured in a way that resists change—not necessarily out of hate, but tradition.
His performance adds balance to the courtroom dynamics, helping the viewer understand both sides of the argument.
Stephen Root as Erwin Griswold’s Colleague
Stephen Root plays a supporting role as one of the senior legal minds aligned with Griswold. He brings both subtle humor and traditionalist tension to the scenes, reinforcing the odds stacked against Ruth.
Chemistry and Casting Excellence
The casting team for On the Basis of Sex did a fantastic job in choosing actors who not only resembled their real-life counterparts but also brought their personalities to the screen. The chemistry between Felicity Jones and Armie Hammer is particularly notable. Their interactions feel genuine, highlighting mutual respect and affection.
Every cast member fits perfectly into their roles, balancing historical accuracy with emotional storytelling.
Why the Cast Matters in This Story
On the Basis of Sex is not just about courtrooms and legal jargon—it’s about human stories. The cast adds emotional weight to legal arguments, making the viewer feel the stakes and the struggle.
This film could have easily become dry or overly technical, but the actors’ performances add life, energy, and emotion to the script.
How the Cast Researched Their Roles
The actors didn’t just memorize lines—they studied their characters thoroughly. Felicity Jones met with Ruth Bader Ginsburg and watched her interviews and speeches. Others read biographies, legal writings, and historical documents to understand the mindset and motivations of the people they were portraying.
Their dedication shows in how authentic each performance feels.
Impact on Viewers and Legacy
The cast’s performances have helped many people—especially younger generations—learn about Ruth Bader Ginsburg and her contributions. The emotional depth added by the actors makes the film educational and inspirational.
Many viewers have said that they came away from the movie not just knowing about legal history, but feeling it. That’s the power of good casting and acting.
Critical Acclaim and Audience Prais
While the movie received mixed critical reviews, the cast was praised almost universally. Felicity Jones received particular acclaim for her nuanced portrayal, and Armie Hammer was recognized for his strong supporting role.
Audiences appreciated the respectful handling of such an important subject, and many noted how emotionally moved they were by the performances.
FAQs about the Cast of On the Basis of Sex
Q1: Who played Ruth Bader Ginsburg in On the Basis of Sex?
A: Felicity Jones portrayed Ruth Bader Ginsburg with grace and intelligence.
Q2: Was the cast historically accurate in appearance?
A: Yes, the casting team chose actors who closely resembled their real-life counterparts and ensured the performances were respectful and authentic.
Q3: Did Ruth Bader Ginsburg approve of the casting?
A: Yes, she gave her blessings to the film and met with Felicity Jones before filming.
Q4: What other movies has Felicity Jones starred in?
A: Felicity Jones is known for roles in The Theory of Everything, Rogue One: A Star Wars Story, and The Aeronauts.
Q5: Is On the Basis of Sex based on a true story?
A: Yes, it is based on real events in Ruth Bader Ginsburg’s early legal career.
Conclusion: A Cast That Honored a Legend
The cast of On the Basis of Sex delivered performances that didn’t just entertain—they honored a legacy. By portraying real people with honesty and emotional depth, they turned a legal drama into a human story that resonates with audiences worldwide.
From Felicity Jones’ commanding portrayal of Ruth to Armie Hammer’s supportive performance as Marty, the entire ensemble brought their A-game. They reminded us of the importance of equality, justice, and perseverance.
If you haven’t watched the film yet, now is the perfect time. And when you do, pay attention to how each actor contributes to telling a story that changed the course of history—on the basis of sex.
