Photo by invisible Harness.

The most beautiful moments of Chamber Music Northwest’s evening with virtuoso pianist Jeremy Denk and his masterful presentation of the almost two-hour long J.S. Bach’s The Well-Tempered Clavier, Book 1 were the end — and the beginning.

The dark and lonely contrapuntal “Fugue No. 24 in B minor, BWV 869,” the last piece of the book, was followed by Denk’s return to the joyful undulating waves of “Prelude No. 1 in C Major, BWV 846,” the work’s first piece. The loop from the last fugue to to the first prelude closed the circle of this remarkable Baroque work written in 1722, 300 years ago. If you know any piece from this collection of 24 preludes and fugues written in every major and minor key, you know the “Prelude in C major.”

Denk, 51, is a deft pianist and natural entertainer. It was clear that he knew how to leave The Old Church audience on Feb. 10 cheerful and utterly satisfied by circling back to the first piece at the end of two hours of concentrated performing on his part and intense listening on the audience’s. CMNW’s co-artistic director Soovin Kim noted before Denk came onstage that the concert in part came about due to his relationship with Denk. The two musicians at the top of their games started their classical music careers about the same time and have played together in countless festivals and recitals.

Denk, who lives in New York and has written an already praised memoir–Every Good Boy Does Fine: A Love Story in Music Lessons, expanded from a 2013 New Yorker article and set to be released in March–has gone on to win the prestigious Avery Fisher Prize and a MacArthur “Genius” Fellowship. He has soloed with the big orchestras throughout the United States (New York Philharmonic, Los Angeles Philharmonic, Cleveland Orchestra and San Francisco Symphony) and abroad; played Carnegie Hall countless times; and doesn’t use a note of written music when he performs this program of Bach masterpieces, designed to teach exemplary pupils back in Bach’s day.

Denk wrote that he became very familiar with the pieces because classical pianists have to drill down on these preludes and fugues as requirements for auditions or qualifying for competitions. “Bach is a great, quick way to judge a pianist’s finger independence, structure and dexterity.”

Denk’s technical skills were reflected in the mighty and relentless pace at which each pair of prelude and fugue was played — the first 12 occurred in about 45 minutes before intermission. But unlike in Bach’s days–when claviers and harpsichords couldn’t reflect dynamics–the Steinway piano that Denk worked over displayed his mastery of and ear for dynamics, which certainly makes the pieces more interesting than when they were played three centuries ago.

Denk took a 12-minute break after the first 12 pieces and played the last 12 in the final hour. The 24 pairs, he playfully explained, bring to mind “animals filing onto Noah’s ark, two of every species, a way to reconstitute musical life should everything vanish.”

Denk is as articulate as he is dextrous, as charming as he is chic. Wearing a European-styled suit and shiny patent leather shoes, he was as magnetic to watch as he was to listen to. His ever-changing facial expressions and acrobatic ways in which he moved his head and torso were off-the-charts expressive, carrying the audience into the pieces’ spirits, without distracting from the music. Then again, if you wanted to zone out on listening to the music, you could zone in on his face.

Speaking of pairs: Bach liked to teach exceptional students, and he and Denk would have been quite compatible. Bach-lovers should be thrilled that Denk is carrying on Bach’s legacy, making the music accessible to those of us not as gifted as he.

A virtual version of the concert is available until midnight March 3 at Chamber Music Northwest.