According to Kinsey, the man responsible for introducing blowjobs and bestiality into the national conversation once couldn’t recognize a chance to score if one walked right up and said how d’ya do. With a bow tie and toothy grin, hopelessly nerdy Indiana University professor Alfred C. Kinsey hardly notices the improbably lit eyes of student and future wife Clara McMillen as he lectures with obvious thrill about his singular passion, gall wasps. And later on campus, when the hard-accented Claaa-ra approaches a lunching Kinsey and kindly asks to join him, the misfit professor reacts not like a bachelor but a scientist: “Why?”

Luckily, Clara (Laura Linney) responds with the appropriate logic, noting that, in the general vicinity, she is the only unattached female and Kinsey (Liam Neeson) is the only unattached male. Romance has little choice but to blossom: In his proposal, Kinsey tells her that she’s “the one girl in a million who’s as interested in insects as I am!” Sex? Well, because both halves of the couple were virgins when they married, not so much.

But the bedroom blues couldn’t have struck more auspiciously: Wondering why their encounters are so painful, the two scholars begin an investigation that will eventually prove the most important sexual organ is the brain. After a conversation with a doctor readily solves their own not-so-little problem—Kinsey is apparently so well-endowed that the physician tells Clara, “I’m surprised you didn’t pass out”—the couple is soon getting down and light bulbs are going off. In essence, Kinsey, an obsessive and hyperorganized gatherer of information, decides to give up bugs for buggery.

Writer-director Bill Condon, who flirted with homosexuality and otherness in his 1998 film, Gods and Monsters, writes in Kinsey’s script, “Love is the answer, isn’t it? But sex raises a lot of very interesting questions.” Not interesting to all, apparently: The film, which opened in limited release last weekend, has already met with protests from people who are against the cinematic celebration of a man they deem responsible for increasing the prevalence of STDs, pornography, and abortions. Still others take exception with Kinsey’s uncondemning inclusion of pedophilia in his groundbreaking 1948 book, Sexual Behavior in the Human Male. Though his portrait here isn’t squeaky-clean—the good doctor uses science to excuse his infidelity, for example, and his work sometimes seems spurred by anger as much as curiosity—Condon is clearly on Kinsey’s side.

Kinsey’s first major step down his fated career path was offering a candid course titled “Marriage,” which countered the university’s laughably misinformed “hygiene” course—portrayed by Condon as complete with apocalyptic films on syphilis and the suggestion that men don’t reach their sexual peak until 40. The ignorance that Kinsey finds among his students prompts him to begin collecting information for what he believed the world was in dire need of: an honest, scientifically accurate sexual reference tool. With the help of aggressively trained research assistants Clyde Martin (Peter Sarsgaard), Wardell Pomeroy (Chris O’Donnell), and Paul Gebhard (Timothy Hutton), Kinsey conducted thousands of pointed, nonjudgmental interviews about the habits of sexually active adults, which he then boiled down into statistics for Sexual Behavior in the Human Male.

These interviews, which Condon films in a quaint, blue-tinted black and white, are scattered throughout Kinsey—both the revealing practice sessions that Kinsey’s assistants conduct with the professor and his wife as well as the talks with real subjects, which are alternately funny, heartbreaking, and squirm-inducing. The same can be said, actually, of Condon’s smart script, which, like Gods and Monsters’, is high on dry, bookish wit. (Kinsey flirts with Clara by reacting to her notion of a gall-wasp Garden of Eden by chiding, “You’ve managed to bridge the gap between Darwin and the Book of Genesis in a single phrase!”)

Though that makes this movie about sex infrequently sexy, it does go a long way toward making it consistently entertaining. From observing Kinsey’s lack of social graces (when a dinner guest gently suggests that he rephrase a comment of “It’s insane,” he comes up with “It’s a really stupid way of looking at things!”) to mocking Dark Ages advice on controlling raging hormones (“Keep your bowels open, read the Sermon on the Mount, keep testicles in a bowl of cold water, think of your mother’s pure love”), Kinsey’s tone is both learned and lighthearted.

As Kinsey, Neeson is a bit of a laugh himself, never shedding the “churchy” demeanor that Clara accuses the character of early in their courtship—even as he’s offering a rapid-fire and impossibly well-enunciated list of acceptable synonyms for naughty bits and dirty deeds. Neeson makes the researcher unquestionably professorial, but with a weird-grin goofiness that nearly belies his unassailable brain. Linney, meanwhile, does her typically subtle work as Kinsey’s patient, open-minded wife and is the film’s most reliable source of playfulness, often talking with a mischievous glint in her eye about the “experimentation” Clara takes part in with her husband. Sarsgaard, too, is strong as Kinsey’s assistant and eventual lover, his sad-eyed Garden State smolder cleaned up but still seductive and deeply felt. Whether Clyde is talking about the heartbreak of his failing marriage or trying to get the boss into bed, Sarsgaard’s underplayed delivery brings the character’s emotional rawness to the surface better than histrionics ever could.

For his part, Condon is a skilled but restrained craftsman, shaping Kinsey’s life into the familiar biopic structure of rise, fall, and rise again. The researcher’s first book is compared to an “atom bomb” and makes him a media darling. His subsequent efforts to dissect the sexual female, however, are met with outrage, with the public claiming that he’s finally gone too far. Of course, Kinsey’s disgrace and subsequent health problems aren’t visited for long before a touching final interview with a middle-aged lesbian (Lynn Redgrave) reaffirms the value of his work. But no matter: Condon convinces nonetheless. When the lights go up, you’ll be disappointed to realize that despite Kinsey’s best efforts, people are still asking the movie’s driving question: “Am I normal?”CP