The lively musical "Thoroughly Modern Millie" opens Thursday in the auditorium at Saucon Valley HS in Hellertown. The popular play, set in New York City during the roaring 1920s, is produced by the Saucon Valley Theatre Department and directed by Chad Miller, a music teacher and first-year director at the high school. A cast of 54 students has just completed a series of dress rehearsals for the production scheduled for March 3, 4 and 5 at 7 p.m. and March 6 at 2 p.m. Ticket information is available at SVSDTheatre.com and 610-838-7001.