“When a woman is frigid . . .” begins a male audience member in archival footage from The Dr. Ruth Show, a 1980s television talk show hosted by this documentary’s subject, sex therapist Dr. Ruth Westheimer. “Hold it!” exclaims the four-foot-nine grandmotherly figure in her German accent. “That word you can’t say on my program.” A feminist icon before the term crystallized in popular discourse, Westheimer is perhaps best known as a media personality who frankly discussed sexual dynamics, AIDS, and women’s pleasure at the height of the Reagan era. But producer-director Ryan White (The Keepers, The Case Against 8), who follows the busy and ebullient Westheimer as she nears her 90th birthday, provides ample space for the luminary to tell her full story. Mostly conveyed through voiceover, with resplendent animation to color in her memories, that journey brims with tragedy and triumph. A self-described “orphan of the Holocaust,” she went on to become an Israeli soldier, a professor in Paris and New York, and the most famous person in America to ask about sex. Westheimer provides an essential public service, which the film, an affectionate tribute to her life and work, continues.