A star-studded, soul-stirring concert by Mavis Staples and Bettye Lavette -- two iconic R&B vocalists, both promoting new albums. This is a one-time joint performance, so it's certainly not to be missed. Saturday, Oct. 9, at 8 p.m. Lisner Auditorium, The George Washington University, 730 21st St. NW. Tickets are $25 to $45. Call 202-994-6800 or visit lisner.org.