ChildhoodfriendsTommyandTuppencemeetinLondonafterhavingservedinWorldWarI.Recentlydemobed,shortofmoney,andwithnojobprospects,theydecidetobecomeadventurersforhire.Soon,theyareemployedbytheBritishGovernmenttolocateasecrettreatysignedbeforethewar.