Everyone came, or so it felt Thursday night at the final concert of the Chamber Music Society's season, featuring pianist Mitsuko Uchida and the Borletti-Buitoni Ensemble, young players supported by an unusual noncompetitive trust that Uchida founded and to which she gives much time and thought.

In the Perelman Theater were pianists, poets, composers, professors and, leaning over the balcony rail, some children. They heard a program more unusual than usual: late Bartok, very late Liszt, and Messiaen's

Quartet for the End of Time

.

The Messaien was the only work in which Uchida graced the keyboard - and I do mean grace. Few play hollow chords with the control to turn them into bells, as she did when backing Christian Poltéra's eloquent cello in "Praise to the Eternity of Jesus" or Soovin Kim's ethereal violin in "Praise to the Immortality of Jesus." In both sections, timelessness was created, a spell of grace that could not exist without the piano's absolute rightness.

Everyone but the pianist gets a solo in the Messaien, yet the piano holds, sustains and frames this universe of a quartet. Olivier Messaien composed it in 1940 in a German prison camp and performed it with musicians he found there. A fine performance will cast a spell. Thursday's was exceptional, the qualities outward and inward, the extroversion particular to the "Interlude" and "Dance of Fury." The clarinet part was taken by Martin Fröst, a charismatic Swiss. His solo, "Abyss of the Birds," moves from triple pianissimos to quadruple fortes with intense, awesome control.

The clarinetist showed another side of his virtuosity in Bartok's

Contrasts

, composed in 1938 for Benny Goodman and violinist Joseph Szigeti. Fröst, Kim and English pianist Llyr Williams, poised and stalwart, made a good team. Williams' interpretation was marked by tremendous fluidity; the violinist, perhaps the most experienced, displayed a delightful splendor of tone, and Fröst's sinuosity matched his charisma. The trio phrased like a fine braid swinging about, and best, they had fun together. Uchida has done well selecting these young artists for the Borletti-Buitoni Trust.

Williams opened with the somber piano solo Liszt began in 1882 and finished in 1885, the year before he died.

La Lugubre Gondola

(The Funeral Gondola) is atypical, spare, with harmonic and melodic dislocations.

Some joked that

La Lugubre

was lugubrious, but young Williams - tall, lean and jacketless, with 1950s specs - played with a bright, earnest, penetrating tone. As he played, one could imagine the composer dissolving the boundaries between sharps and flats, and maybe between life and what comes after.

Farewell to society events until October. But there is always Vermont, and the summer's Marlboro Chamber Music Festival. Uchida and pianist Richard Goode are its co-artistic directors. Kim will be playing there this summer, too. Check the Web site.