Signature Theatre in Arlington, Virginia mounts a gorgeous, first-class production of Stephen Sondheim and James Lapine’s 1994 Tony-winning best musical, “Passion”, featuring striking and beautiful designs, lush instrumentation, a full-voiced ensemble, and notable performances by Natascia Diaz and Claybourne Elder.  If you live in the D.C.-metro area, or will be passing through, be sure to check out this rarely seen chamber-sized musical melodrama.