Centuriesbeforetheworld'soceansbecameaglobaltradehighway,Chineseseafarerssetsailtofarawaylandstoexchangecommodities.Now,HistorianSamWillisretracesthegoldeneraofmaritimetradetouncoveralegacythatculminatedinoneofthegreatestarmadasofalltime,anddiscoverparallelsbetweentheworldthenandnow.