The Utah Symphony presents its annual "Messiah" Sing-In this weekend, with the audience in Abravanel Hall joining the orchestra and Utah Symphony Chorus in a dozen choruses from Handel's popular oratorio. Music director Thierry Fischer conducted the event this year, and 100 volunteer singers from the Mormon Tabernacle Choir were scattered among Saturday night's audience to give less-confident singers a boost. Singers from the University of Utah were scheduled to join the crowd for Sunday night's performance.