From Eipix, in partnership with Big Fish and the Smithsonian Institution, comes the epic continuation of the Hidden Expedition series! Your old buddy and H.E.L.P. operative Sam calls you in to investigate a strange anomaly at the Smithsonian Castle. You soon learn there's more to this anomaly than meets the eye, and H.E.L.P's reach stretches back to the Smithsonian's historic founding. Unlock the secrets of time travel as you follow the clues into the Smithsonian Castle's Civil War past.