The Frick Collection chose an appropriate moment to mount “Jean-Etienne Liotard (1702-1789): Swiss Master.” The contemporary-art world is awash in figurative art, and this exhibition – the first of its kind in North America – dovetails with the renewed interest in representation. Now that more gallery-goers want to look at images of people, a fresh audience for Liotard’s gorgeously idiosyncratic work could emerge.

Liotard was not satisfied with saccharine gloss or subjective treatment of the sitter. His brand of portraiture, devoid of surface flourishes and narrative props, stands in stark contrast to the vacuous work of contemporary painters like Elizabeth Peyton and John Currin. His scrutiny reflects the empiricism of the Enlightenment – refusing to trade fact for fiction – while his work anticipates the modernity of Cezanne through its compositional clarity, straightforward use of material, and commitment to the act of looking.

Lining two walls in this exhibition of 51 works are haunting portraits of the Austrian imperial children, commissioned by Empress Maria Theresa in 1762. The veracity of these drawings is exhilarating: Their stark matterof-factness and lack of flattery impossibly oozes royalty.

The image of Archduchess Marie Antoinette at age 7 is particularly fascinating, as much for our awareness of her eventual demise as for her starchy countenance. Her ice-blue eyes, too old for that delicate little body, are tense with her renowned highmaintenance personality. Hanging immediately to her right is a portrait of 6-year-old Archduke Maximilian Franz, the youngest of the imperial children. He stands with back straight and chest puffed out, his proud, dopey innocence offering a wry contrast to Marie Antoinette’s deep self-awareness.

Liotard’s pictorial approach was rooted in his training as a miniaturist. Studying under Jean-Baptiste Masse, he was encouraged to experiment with various mediums, and to combine several techniques in a single picture. Often on the verso of his drawings, such as the portrait of Archduchess Maria Theresa, Liotard added flat swaths of pure color to achieve an amplified sense of relief, like a spatial haloing. But it was his singular use of pastel that distinguished him from his peers.

Prior to the 18th century, pastel was rarely used, and only as a final process to add highlights. Its earliest historical notation is found in Leonardo da Vinci’s “Codex Atlanticus,” which indicates that Jean Perreal brought the new material to Milan from France in 1499. Because of pastel’s advantageous qualities, like reworkability and lightfastness, its popularity exploded in the 18th century, especially among French School artists Jean-Marc Nattier and Maurice Quentin de La Tour.

Unfortunately, the fragile nature of Liotard’s pastels prevented the Frick from obtaining more than a few examples of his genius in this dry, chalky medium. His popularity does not have the legs it deserves outside Europe primarily because of the work’s relative inability to travel.

“Liotard With a Beard” (c. 1749), a large self-portrait greeting viewers at the beginning of the exhibition, is one pastel that did make the trip. Dressed in primary-colored Turkish garb, Liotard sits at an easel, a pastel in his right hand scrupulously recording his image. His features appear to be incised out of putty; deep wrinkles and hundreds of perfectly defined gray hairs are testament to his belief in an unflinching, often unflattering, gaze.

Here, Liotard corrals pastel into a synaesthetic experience; his unfailing observation and precision of line enables this image to shift from a mimetic depiction of the sitter to a full-body experience for the viewer. His red jacket prickled my skin; my nose smelled his eyes and slightly parted lips; his beard filled my ears with incense.

The Middle Eastern persona Liotard adopts in “Liotard With a Beard” was a branding device the artist cultivated following his four-year sojourn to Constantinople between 1738 and 1742. Tapping into Europe’s fascination with the East, he morphed into an exotic oddity and became known as le peintre turc – a stunt that earned him many commissions. Imagine the titillation of having your portrait made by such an eccentric!

A hint of the sitter’s effervescence comes through in each Liotard portrait. In “Grace, Countess of Clanbrassill” (1774), the sitter’s curious eyes reciprocate Liotard’s studying gaze. The faint, erotically tinged smile crossing her lips confesses her happiness at the whole affair.

Though financially successful, Liotard remained an enigma, a true outsider. His work never fell into step with the Rococo and Neoclassical styles; he was disregarded by the major artists of his day and had no students or followers. The French Academy flatly rejected him. Was he genuinely crazy?

The late self-portrait “Liotard Laughing” (1770) suggests he understood and accepted life’s absurdity. Dressed in a red fez and blue jacket, the 68-year-old artist invites us to laugh with him. His face is punctuated with a silly, gap-toothed grin, telling us to proudly accept the reality of our all-too-human bodies. His right hand points to something unseen, just out of the frame, posing the ultimate question from someone obsessed with verisimilitude: Is there something more than appearances?

Until September 17 (1 E. 70th Street, between 70th and 71st Streets, 212-288-0700).