Many people have a specific reaction upon seeing an America $2 bill. Because cash registers don't have a slot for them, most retailers don't stock them and you rarely see them in change. The bills have an air of mystery and mystique because of their rarity.

However it really is just a myth. The bills are actively being printed and are truly not rare collector's items. They're worth exactly $2 and you can get them as most banks.

But there is a real and fascinating mystery when it comes to those $2 bills. And that's the Founding Fathers who are pictured on the note.

The front it easy and obvious. It's Thomas Jefferson, the 3rd president of the United States. The reverse of the bill is a version of a painting called Declaration of Independence. It was painted in 1818 and has been displayed in the Capitol Rotunda since 1826.

With so many people depicted from the scene inside Independence Hall in Philadelphia, the Government Printing Office created a who's who guide to the painting. Here's the trouble. The depiction on the back of the $2 does not match the painting. There are some men who were removed from the $2 due to space constraints. But, somewhat inconceivably, there where 2 phantom men added where they do not appear in the painting.

two unrecognized figures were added: one in between Samuel Chase and Lewis Morris and another between James Wilson and Francis Hopkinson

Who are these men who showed up on the back of the $2 note? They've never been identified. Likely they were figments of the engraver's imagination.

A wonderful guess comes from a Redditor who commented when the subject came up on r/PaperMoney subreddit recently attributing the phantom face to that of Count of St. Germain, a French aristocrat who has become a figure of legend based on his suspected immortality.

Next time you come across a $2 bill - or pull out that stack you have stashed away somewhere, you know you have one - take a look at the back and know that there are two mystery figures that no one has ever identified that were supposedly at the scene of the crafting of the Declaration of Independence.

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