Tazewell Thompson, who got his start at Washington's Arena Stage, now travels the globe to direct both theater and opera. He made his Baltimore debut this year with a stunning mounting of Lynn Nottage's "Ruined." It's a play in which the joys and horrors of tropical Africa alternate in brisk succession. Thompson used the regular eruption of dancing to make the joy contagious and generated the shock of offstage violence by abruptly imposing stillness on the room just as often. Each of his actors had to make similarly sudden transformations, and Thompson guided them through those changes without a false note ever betraying the before or the after.