Looking for Answers about Barbour Publishing #2: Sydney's D.C. Discovery?

Danger lurks in the nation's capital. Something strange is going on at the Vietnam Memorial. Orange graffiti, secret messages, suspicious looking characters, and mysterious items left at the foot of the wall. Sydney and Elizabeth begin an adventure that leads them through Washington, D.C., up to Fort McHenry. Will the Camp Club Girls unravel the confusing clues at the twilight's gleaming and deflect any danger before the dawn's early light?