GEOFF BENNETT: The great painter John Singer Sargent, an American expat, is the subject of a new show at Boston's Museum of Fine Arts, its only U.S. location before moving to London.

It reveals much about his methods and why his work remains relevant more than a hundred years later.

Special correspondent Jared Bowen of GBH Boston reports for our arts and culture series, Canvas.

JARED BOWEN: Painter John Singer Sargent had a way, a way of rendering the architecture of an arm, a splaying of the fingers, or an elevation of the chin so that we could know exactly what he saw inside and out.

ERICA HIRSHLER, Senior Curator, Museum of Fine Arts Boston: There's some people who recalled that they saw a little bit too much and that it was a little bit nervous-making to go sit for Sargent.

JARED BOWEN: Sargent was an American artist who became the darling painter of the upper classes on both sides of the Atlantic from the late 1800s through the turn of the century.

His sitters had noble lineages and cascading jewels and paid six figures in today's money for the privilege of being painted by him.

ERICA HIRSHLER: He decided how they were going to pose, what they would wear in many cases and the backdrop and setting.

JARED BOWEN: Erica Hirshler is the curator of Fashioned by Sargent, a new exhibition at the Museum of Fine Arts Boston that follows the threads of Sargent's process, even reuniting portraits with the original garments his sitters wore, like this opera cloak enveloping Lady Sassoon.

ERICA HIRSHLER: He takes it and he pulls it across her body, and he turns out the lapel, so that you get this great swoop of pink satin across her body.

And it makes for a much more interesting painting.

JARED BOWEN: While the society portraits may have been Sargent's bread and butter, his true nourishment came from society's fringes.

He relished painting bohemian poets, playwrights and musicians.

And, here, Sargent was as drawn to Ellen Terry as Lady Macbeth as he was to her costume.

ERICA HIRSHLER: The costume is covered with beetle wings, which reflect the light and sort of shimmer blue-green.

And the excitement of being able to paint something that was so unusual appealed to him.

PAUL FISHER, Author, "The Grand Affair: John Singer Sargent in His World": I think there's a lot of Sargent's biography lurking in these paintings.

JARED BOWEN: Paul Fisher is a Wellesley College American studies professor and author of the recent Sargent biography "The Grand Affair."

Far from the Gilded Age drawing rooms, he says the painter was also drawn to the transgressors, and had the daring to paint them, and all at a time, not unlike today, when society was publicly wrestling with gender fluidity.

PAUL FISHER: Newspapers of the time often described this as the maladie du siecle, the illness of the century.

Women were out and about.

Men were seen as more complicated, maybe more effete.

So there was a lot of anxiety.

And Sargent capitalizes on that.

JARED BOWEN: He did it boldly in this portrait of a well-known Parisian, the gynecologist Dr. Pozzi.

For its startling intimacy, the painting was never shown publicly in Paris in Sargent's lifetime.

PAUL FISHER: He's wearing a blood-red robe.

And he's got cuffs and a collar that are highly pleated and somewhat feminine.

So, Sargent is really sporting with gender here.

Dr. Pozzi was a famous womanizer, but he had lots of queer friends in the circles in Paris.

And Sargent was kind of gripped by this man's charisma, and you can see it in the portrait.

He has warring instincts.

On the one hand, he's a very sort of shy, quiet, retiring man who loves his work.

On the other hand, the provocation is part of his making a career for himself.

JARED BOWEN: But provocation doesn't even begin to describe what Sargent did in 1884, when this portrait of the American-born Madame Pierre Gautreau was exhibited at the prestigious Paris Salon.

She did not commission Sargent.

Rather, he chased her.

ERICA HIRSHLER: Everybody in Paris wanted to make an image of Madame Gautreau.

One other American artist described her as black as spades and white as milk, and she sort of glided across the floor.

JARED BOWEN: But when the portrait was unveiled with Gautreau's revealing gown, one strap originally painted slipping down her shoulder, and her skin so white it looked lavender, society revolted.

ERICA HIRSHLER: One of Sargent's friends wrote that it was surrounded by shoals of jibing women.

And also, in the press, they say that it looks like her dress is about to fall down.

They say she looks like a corpse, she's so pale.

JARED BOWEN: Gautreau was mortified and Sargent was singed.

He later repainted the strap and found the experience bruising enough to leave Paris for London.

ERICA HIRSHLER: Sargent, when he sold it to the Metropolitan Museum in 1915, he said: "I think it's one of the best things I have ever done."

It's interesting.

She sort of retreated from society, but then, some years later, had another portraitist paint her portrait also in profile, also with one strap down.

JARED BOWEN: And validating John Singer Sargent as both socially and fashion-forward.

For the "PBS NewsHour," I'm Jared Bowen in Boston.