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the story behind the book

Kristie Macrakis explores secret messages, invisible ink

20storybehind credit David Wilso

Raised in Belmont and Cambridge, historian Kristie Macrakis never met a spy until she moved to East Germany to conduct research for her dissertation. “Germany is the land of spies,” she says, especially in those years before the Berlin Wall came down. “Berlin was like a spy novel.”

Intrigued by the idea of espionage and spycraft, Macrakis wrote a book about the Stasi, the now-defunct East German secret police agency, focusing on its use of technology in espionage. While in the Stasi archives, she found something that made her heart beat faster: a formula for invisible ink.

Of all the spycraft that fascinates Macrakis, now a professor at Georgia Tech, secret writing has perhaps the longest history. “It goes right back to the ancient Greeks,” she said, adding that at times it has changed the course of history.


Macrakis tells the story in her new book, “Prisoners, Lovers, and Spies: The Story of Invisible Ink from Herodotus to al-Qaeda.” Using a hidden message carved in wood, then coated in wax, an exiled Spartan warned his countrymen of a planned Persian attack, Macrakis says.

Without the warning, “the Greeks would have lost their battle against the Persians. Greek civilization would have diminished and other civilizations would have flourished, and human history would have looked very different.”

Nowadays, of course, secret messages are often hidden in electronic or digital form — “ancient Greece reincarnated,” Macrakis says — but although the technology may change, the idea behind it does not.

She has no doubt new stories are yet to be told. “That’s the thing with invisible writing — just because you don’t find it doesn’t mean it’s not there. The challenge writing the book is that I’m sure half the stories aren’t there, because they’re still hidden. If it’s good secret writing, you never find out about it!”


Macrakis will read Tuesday at 7 p.m. at Harvard Book Store.

Kate Tuttle can be reached at