Film and book each reveal the extent to which Martin Ginsburg devoted his life to ensuring that child-rearing, housework, and legal accomplishments were shared between them. (He did the lion’s share of the cooking—and, as the film portrays it, was the gentler, less demanding parent to their tempestuous daughter, Jane.) Their dedication was mutual. When he was diagnosed with cancer while attending Harvard Law School, Ruth kept up with his assignments and helped him with his papers. Traditional this was not: Marty’s insistence on seeing his wife as his professional and intellectual equal was inconceivable for the time, and even 50 years later, his breed of super-booster is hardly the norm. Ruth’s meteoric career was inspired and enabled by the rarest of male allies.

The rest of the world was not so accommodating, and Ginsburg coped with and chafed at, however quietly, the obstacles in her way. Her response, in De Hart’s portrayal, was intensity, as opposed to anger, because it was abundantly clear that anger would be disqualifying. (In On the Basis of Sex, she allows herself to vent her frustration only a few times—primarily at teenage Jane.) She was stellar wherever she was—ranked near the top of her class at Harvard Law, and on the Harvard Law Review, and then tied for first place in the 1959 graduating class at Columbia Law School, where she transferred after Marty, already armed with his law degree, got a job in New York. But she could barely win a clerkship and could not land a law-firm job. “To be a woman, a Jew, and a mother to boot,” she would later quip, was “a bit much.”

Ginsburg accepted a job teaching at Rutgers Law School and soon proposed a course on gender-discrimination law (which a male faculty member at NYU had earlier suggested would be as useful as a class on bicycle law). Before long, she was an expert on the subject. When Marty happened upon a tax-court ruling in 1970 about a man named Charles Moritz, a grand litigation strategy was born in the Ginsburg household. The IRS had determined that Moritz, an unmarried salesman from Colorado, couldn’t deduct the salary he paid a nurse who cared for his invalid mother because he was a son, not a daughter. This policy, the Ginsburgs contended, assumed that women were caregivers while men worked—a gender stereotype that violated the equal-protection clause of the Constitution. Backed by the American Civil Liberties Union, their appeal—at the dramatic heart of On the Basis of Sex—became the template for the constitutional revolution that demolished hundreds of laws rooted in archaic ideas about women’s limitations.

In 1972, Ginsburg was chosen to lead the ACLU’s newly created project on women’s rights. Building on Moritz v. Commissioner of Internal Revenue, Ginsburg got to work, in the process dismantling assumptions about women and the ways in which they worked, were paid, and were entrusted with responsibility. From De Hart’s accounts of appeal after appeal, oral argument after oral argument, the enormity of Ginsburg’s project emerges: Every case was selected and framed as part of a careful campaign. In a battlefield of words, laws, and doctrine, Ginsburg was the general. But hers wasn’t an angry, violent advance. Her ambitious approach was designed to inch the Supreme Court into requiring formal legal equality for women. And at every turn, Ginsburg also had to face professional slights and sexist assumptions within her own profession, directed at her personally. In a chilling moment in the film, the legal director of the ACLU (and her friend) snarls, during a disastrous practice session for an oral argument in Moritz, “Would it kill you to smile?”