MADISON, Wis. -- A Wisconsin woman's amazing story stretched beyond the U.S.'s borders to Nazi Germany, where she became a major force in the underground resistance to the Nazis and personally caught the attention of Adolf Hitler.

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The true scope of Mildred Fish-Harnack's story could only be discovered after the fall of Communism and the opening of KGB and CIA files.

There are honors and accolades for her across Europe, and even a school named for her in Berlin, but in Wisconsin she is all but forgotten.

"Yes, I really think you can say she was and she is a German American hero," said Johannes Tuchel, director of the German Memorial Resistance Center.

At the turn of the century, Mildred Elizabeth Fish grew up in a working-class neighborhood around 26th and Highland on Milwaukee's West Side.

In the 1920s, her courageous journey into Nazi Germany started with a mix-up in Madison. Graduating from the University of Wisconsin-Madison in 1925, it's easy to pick her out of the yearbook. Mildred Fish is the only one with her picture in profile, and with her beauty and poise, those who knew her said Mildred stood out.

Staying to attend graduate school, she shared an office on the third floor of Bascom Hall and taught modern American literature.

Art Heitzer, Wisconsin's resident expert on Mildred Fish, said that is when a young scholar arrived from Germany.

"Arvid Harnack was from a blue chip intellectual family of Germany," Heitzer said.

Heitzer said a simple mistake changed everything when Arvid mistook Bascom Hall for Sterling Hall, landing in a lecture on American literature by Mildred Fish.

"And he was charmed, even though he didn't know English that well and wasn't sure he understood everything she said," Heitzer said.

Their courtship began with canoe rides out to Picnic Point and lunch on State Street, leading to a wedding that same year on her brother's farm near Evansville. In 1929, she moved with her husband to Germany, where Mildred taught at Berlin University and Arvid found a government job.

Despite having work, times were tough under the Nazi dictatorship. During the war, Mildred would forage for food on the streets of Berlin.

Tuchel said that Mildred was anti-Nazi from the beginning.

"From the first day of the Nazi period, Mildred Harnack was against this dictatorial system," Tuchel said.

The Harnacks used her third-floor apartment on Woyrschstrasse to put their resistance into action, seeking to end the war and preserve German independence. They recruited other like-minded Germans and began spiriting military and economic secrets to the United States and Soviets.

The Nazi resistance circle was nicknamed the Rote Kapella or Red Orchestra, WISC-TV reported.

"It's a Gestapo name, in the language of the Gestapo. Red is a clear reference to a kind of Communist," Tuchel said.

The moniker also represented the group's clandestine transmitters. The short-wave radios used to broadcast secrets to the Soviets were called pianos and their operators were referred to as musicians.

"Mildred Harnack was one of the forming members of the Red Orchestra," Tuchel said.

Mildred and Arvid's close friends said they weren't Communists.

So while Americans listened to radio addresses, Mildred would translate those speeches from U.S. President Franklin Roosevelt and British Prime Minister Winston Churchill and then leaflet the illegal messages around Berlin.

Some even credit Mildred with being the first to warn the U.S. embassy about the terror of National Socialism.

The Harnacks had a close friendship with Martha Dodd, the U.S. ambassador's daughter.

"There was quite a societal circle going on there, embassy parties," Heitzer said.

"She was involved in the close contacts with members of the American Embassy here in Berlin to give them information on the German war plan," Tuchel said.

Arvid also had regular rendezvous with the U.S. embassy's first secretary, Donald Heath, to provide information on Germany's currency and bank holdings.

"Heath was actually head of the embassy at that point and they had very close contacts, exchanged perspectives, views and information. There's no question about that," Heitzer said.

As the war raged on, the Harnacks' work became increasingly dangerous. In August 1939, the embassy advised all Americans to get out, and Arvid bought Mildred a ticket home -- but she refused.

"She decided to stay here with her husband to fight against the Nazi dictatorship," Tuchel said.

But their demise began in 1942, when the Soviets lost contact with the group and then transmitted the names of three Red Orchestra members, including the Harnacks' address, to a Soviet spy in Brussels.

"In the summer of 1942, the Germans were able to read these communications from Moscow to Brussels and so they were able to identify the addresses," Tuchel said.

At a fisherman's cottage in Preila, East Prussia, the Gestapo arrested Mildred and Arvid during a weekend trip 65 years ago.

The secret police brought the Harnacks to the most feared address in Berlin, the Gestapo headquarters at Prinz Albrecht Strasse No. 8.

"Between 1933 and 1945, about 15,000 persons were arrested and interrogated there," said Andreas Sander, German researcher and curator of Topography of Terror.

Sander said that inside the building were 38 solitary cells and interrogation rooms where both Mildred and Arvid were tortured.

"While there are different forms of torture, I think every type of torture you can imagine (occurred)," Sander said.

The Gestapo was brutal in its interrogations, and Walter Habecker, known for his torture techniques, was assigned to break Mildred Harnack.

Women were treated no different than men, and survivors said they witnessed the horrors.

"She became seriously ill, and one person said she was brought here lying on a stretcher to the interrogation one day," Sander said. "Some inmates committed suicide here because they don't want to give information about their group."

There are unconfirmed reports that Mildred tried to commit suicide by swallowing pins.

In the months to come, 117 members of the Red Orchestra were arrested and tried at the Reich's Military Tribunal. The trials were shrouded in secrecy and a death sentence was almost assured.

"The family in Germany to some degree knew that they had been arrested but were under strict orders that if you tell anyone, you will be in very big trouble," Heitzer said.

On Dec. 19, 1942, guilty verdicts were delivered against 13 so-called Red Orchestra members. Arvid was sentenced to death for high treason and espionage. Mildred was sentenced to six years in prison.

Arvid was relieved, thinking that she could survive prison and live to see a free Germany.

"They both were convinced that that regime was not going to last," Heitzer said.

While in prison, Mildred became very sick with tuberculosis. But the secret police wouldn't transfer her to a hospital because it might create a window of opportunity for a relative to intervene. It also prevented the U.S. government from intervening, since she was a U.S. citizen with a valid passport.

No family member was ever granted permission to see her again, and some said it was because she was an American.

Habecker, Mildred's main interrogator, was eventually arrested by the British on Jan. 25, 1945. Four years later, while in prison, Habecker committed suicide.

Today, the neighborhood where the Harnacks lived is still anchored by the little red church that stood when the couple called that street home. After their arrest, their apartment was seized and given to the family of a German storm trooper.

The apartment was destroyed during an Allied bombing raid in 1944.

NOTE: WISC-TV and Channel 3000's special series "Mildred Fish Harnack: Back To Berlin" continues Wednesday night on "News 3 at 10: The Update." Wednesday's segment will examine how Hitler personally intervened in the case of Mildred Fish-Harnack.