CAMBRIDGE - The chorus Stile Antico has, in a remarkably short time, gone from being a rookie on the early-music scene to one of its MVPs. Made up of 13 astonishingly talented British singers, the group has injected a dose of emotional intensity into its performances of Renaissance polyphony, music often presented with a cool, distant beauty. Stile Antico made its US debut last year at the Boston Early Music Festival; on Friday, the festival led off its current concert series with a return visit. Judging from the large and attentive audience that filled St. Paul's Church for this remarkable concert, the secret about the ensemble is out.

Part of what makes Stile Antico so compelling is that the group works without a conductor, so a performance gives the sense of an intimate conversation among friends. On Friday, that conversation touched on profound matters: The program, 'In Paradisum,' focused on swan songs and memorials by Renaissance composers. Intimations of death were everywhere, whether in the transfixing sweetness of Byrd's 'Retire my soul,' the opener, or Dufay's more intricate 'Ave regina caelorum,' which he composed to be sung around his deathbed. Both were impeccably tuned and balanced, and the Dufay featured some unusual harmonic passages.

The long work on the program was John Sheppard''s monumental 'Media vita,' at around 25 minutes, one of the largest unbroken movements of a cappella singing produced in the Renaissance. It's difficult to imagine a better performance of this exhausting work; it was not only beautifully sung but perfectly structured, with careful attention to phrasing, bringing a listener from its hesitant opening to a spiritually ecstatic close.

The second half featured more diverse fare, from Josquin des Prez's 'O bone et dulcissime Jesu' to Alonso Lobo's haunting 'Versa est in luctum.' The ensemble's vocal blend, warm and rounded, occasionally shifted to allow the colors of individual voices to emerge.

Scütz's 'Herr, wenn ich nur Dich habe,' familiar as the second movement of his 'German Requiem,' was presented in an austere reading for eight voices that seemed to reach more deeply into the text's meaning than larger-scaled versions. Lassus's 'Vide homo,' which ended the program, cloaked stern admonitions in Jesus'' voice in some of the richest and most rhapsodic harmonies heard all evening.

A standing ovation elicited an encore: Byrd's Nativity-themed 'Ecce virgo concipiet' - a nice change of pace after an evening pervaded by death.