The team at the Potomack Company auction house knew they had something special: a 1780 letter from Alexander Hamilton to the Marquis de Lafayette. The Founding Father had written to the French commander warning about the British naval fleet. Given the new-found appreciation of Hamilton (see: the smash Broadway musical), curators estimated the letter could sell for $US25,000 to $US35,000 ($36,000 to $51,000) or a lot more if a bidding war broke out.

And then, just like Hamilton's tumultuous life story, there was a dramatic twist: the letter was authentic and a valuable piece of American history. But it was also stolen.

Washington Post