The Silent Cipher

Unveiling Agent 355 and America's Forgotten Spy

Uncover the Revolutionary War’s Most Elusive Spy… A Woman Known Only by a Number.

She had no name. No face. No known past. And yet, the fate of a nation depended on her silence.

During the bloody crucible of the American Revolution, amidst betrayal, redcoat raids, and secret networks of rebel informants, there existed one spy so vital to Washington’s intelligence operation that her identity remains shrouded to this day.

She was known only as: Agent 355.

In The Silent Cipher, acclaimed historical nonfiction author Evelyn J. Harding plunges readers deep into the clandestine world of 18th-century espionage—reconstructing the secret lives, whispered codes, and invisible wars that shaped America’s birth. This is not a mythologized tale. It’s a pulse-pounding investigation grounded in archival letters, decoded ciphers, and firsthand accounts—all pointing to the undeniable truth that one woman helped turn the tide of a revolution, and then disappeared from history.

A Story Hidden in Plain Sight

From the dangerous streets of British-occupied Manhattan to the covert safehouses of the Culper Ring, this cinematic true story follows the threads of a woman who walked among traitors and tyrants—a shadow in the enemy’s court. As General Washington built a spy network beneath the noses of the British, Agent 355 risked everything to deliver intelligence that saved American lives.

But who was she? And why was her name erased?

Was she a loyalist’s daughter turned rebel informant?
A laundress in a British officer’s home?
A woman trained in tradecraft decades ahead of her time?
Or was she more than one person—a composite ghost created to protect them all?

Harding exposes the startling truth behind the legends.

Why This Book Matters Now

In an era when history is being re-examined through new lenses, The Silent Cipher reclaims the voice of a forgotten patriot. Agent 355 isn’t just a historical curiosity—she’s a symbol of the invisible women who shaped history, who spied, fought, and sacrificed without credit.

This book is for:
- Readers of Erik Larson, Nathaniel Philbrick, and Kate Moore
- Fans of Cold War espionage who crave deeper roots of spycraft
- Women’s history advocates seeking stories of courage erased by time
- American history buffs who think they’ve heard it all—until now

Inside the Book:

- The Culper Ring: How Washington built America’s first true spy agency
- British counterintelligence tactics—and how 355 evaded them
- The secret communications network used to smuggle coded letters
- A forensic investigation into the candidates who may have been Agent 355
- The shocking link between her final mission and the death of Nathan Hale

What Early Readers Are Saying:

"Reads like a historical thriller—but it’s all true. A woman history tried to erase finally gets her voice back."
— Historical Times Review

"A fascinating dive into America’s first spy ring—and the forgotten heroine behind it. I couldn’t put it down."
— Claire H., Revolutionary War Archivist

"Absolutely essential reading for anyone who wants to understand the birth of American intelligence—and the role women played in it."
— Lt. Col. M. R., U.S. Army Intelligence (Ret.)

Dare to Enter the World of the Unseen

The Silent Cipher is not just a biography—it’s a bold act of historical recovery. Through every page, Evelyn J. Harding breathes life into the silent pages of America’s founding and gives voice to the spy who never broke hers.

History tried to forget her. This book won’t let you.