The millions of tourists who visit the Smithsonian Museum each year see a number of exhibits that are enough to impress most people. But there's a secret vault at the museum that houses some of the coolest stuff in the Smithsonian's collection. These hidden storerooms aren't meant to be seen by the general public, but in this series, host Xavier Carnegie -- the creative director at the National Museum of American History -- gives some unsuspecting Smithsonian guests the opportunity to enter those vaults to witness hidden gems firsthand.