Patricia Kopatchinskaja, a violinist from the Republic of Moldovia (between Romania and Ukraine), plays barefoot. She is known for her eccentric, brilliant interpretations of Beethoven—the Violin Concerto with Philippe Herreweghe and the Orchestre des Champs Elysées, and the Kreutzer Sonata with Fazil Say. In fact, the pianist was so enchanted with her playing that Say composed his “1,001 Nights in the Harem” Concerto for her—that's quite something, considering he has also successfully teamed up before with Maxim Vengerov, no less.

On June 9, Kopatchinskaja—or PatKop, as she’s called on her website—joined Say for an hour-long guest spot during his all-night “residency” at the Konzerthaus Berlin (“Die Lange Nacht des Fazil Say”).

There were no program notes. No one knew what to expect. All it said in the program booklet was “works by Wolfgang Amadeus Mozart, Maurice Ravel, Béla Bartók, Dave Brubeck, Fazil Say, among others.”

Kopatchinskaja came on to the stage wearing a burgundy boho-chic sleeveless gown with black lace accents. No shoes. Speaking into a microphone, Say introduced his duo partner (they’ve been together since 2006), and said with a smile, “first she will play a piece lasting approximately one minute and then you will know who she is.”

Jorge Sanchez-Chiong’s “Crin” (1997) is a manic explosion of slides, left-hand pizzicatos, and ricochets (a little like Sciarrino’s music) combined with nonsense words and percussive sounds made with the voice. Crazy virtuosity. Pure theater. Kopatchinskaja nailed it, and even made us laugh as she pointed the bow directly towards the audience and said, “Pah!”

The atmosphere was electric. Of course, there were no program notes. Who could look away, even for a moment?

She was totally riveting.

Say announced all the pieces from the stage. The first piece they played together was the “Blues” movement from Ravel’s Sonata. They played so well together it was as if they were magnetically connected. She added notes to the violin line, Gypsy-style turns and runs, all intuitive and natural.

The word dynamic doesn't even begin to cover it.

A free spirit, she turned her back to the audience to lean into the piano in defiance of convention, if the music called for it. And yet—and this was what’s so exciting about her—it’s not all about her. It’s all about the music: she embodies it, she becomes it, she is it.

She played Bartok’s Rumanian Dances like you’ve never heard them before, full of earthy rhythms and Gypsy-ish improvisations that came naturally to her, having been born into a family of Gypsy musicians, but also with the technical mastery and golden sound of a top soloist.

And then there's Fazil Say’s Violin Sonata, in three movements, which calls for beautiful sotto voce melodic playing at one extreme and, at the other, a col legno ricochet down-bow stroke so diagonal that by the time she reached the point of the bow, it was bouncing on the fingerboard almost at the scroll.

Just as spectacular was “Cleopatra,” a solo piece also composed by Say for a competition and then edited by Kopatchinskaja. It has a recurring pizzicato theme, recitatives packed with augmented seconds and tritones (much in the style of the “1,001 Nights” Concerto), an amazing tremolo/trill effect in double-stopped glissando sixths, and a perpetuum mobile section near the end.

This last piece ends ppp with a pizzicato, and she looked up on the last note with a look of shocked surprise, for theatrical effect. She performed like a theater person—an actor—or maybe even a mime.

The same was said about Paganini.

Her vertical axis was about as contorted as Paganini’s was supposed to have been, as well. Her body snaked around making improbable movements—how did she play like that? —and yet she and her violin moved magically as one.

For the remainder of the set, they were joined by the wonderful Turkish percussionist Burhan Öçal for Say’s original arrangements of Mozart’s “Rondo alla Turca,” Paganini’s Caprice No. 24, an excerpt from Say’s own Violin Concerto, and Beethoven’s “Für Elise.”

While Say and Öçal improvised a dialogue, and Öçal took a solo, the violinist sat on a step on the stage, one leg crossed, chin in hand, bobbing her head in time with the music—no precious diva-ish stage exits at the risk of interrupting her companions. In fact, the final stage exit was playfully done, “Farewell Symphony-style,” with her and Öçal walking off still playing their instruments sempre diminuendo, leaving Say alone at the piano.

There will be those who claim her playing is not to their taste—she’s yet to record any Bach, for example—yet I think it would be hard for anyone to deny that she has some special quality. She could be crazy or a genius, maybe both. Still only in her mid-30s, she is without a doubt the single most exciting violin talent I’ve even seen emerge.

Wow.