Artemis Joukowsky was just 14 when he heard the dreaded diagnosis. Doctors told him he had spinal muscular atrophy — a debilitating genetic disorder that limits muscle movement, caused by a loss of nerve cells from the spinal cord. Many people die from the disease, and those who don't could still lose the use of their legs, and sometimes other parts of their body.

He remembers being in the hospital terrified in New York when his grandmother came in — Martha Sharp-Cogen, the unconventional woman who had gotten divorced, run for Congress, attended glamorous balls, and owned a castle.

"She came in to see me in the hospital. And she said: You know what? We're not going to feel sorry for ourselves. We're going to continue help other people. Don't focus on yourself. Focus yourself on helping others."

It was advice that might have been viewed as 'tough love' in another context. But for Joukowsky, the advice struck a chord. If there were ever examples of overcoming challenges and helping others, it was his grandparents, Martha and Waitstill Sharp.

Only a few months previously, Joukowsky had interviewed Martha as part of a school project to find stories about "moral courage." Prodded by his mother to interview his grandmother, who did some 'pretty cool things during the war' to help the Jews escape the Nazis, Joukowsky arranged to interview Martha — or "Mummy Mummy" — as he knew her, and was bowled over by her secret past.

While raising two small children in a middle-class U.S. family, Martha Sharp and her first husband had gotten involved in secret, highly dangerous missions to Europe to save Jews from certain death in Nazi camps. And his grandparents weren't trained CIA spies or government agents. They were just a church minister and his spouse, risking everything and ultimately sacrificing their own marriage to help total strangers evade a fascist regime. Joukowsky decided at that moment that his grandparents' story would be told one day, and that he would be the one to piece together the fragments from their lost past.

Buoyed by his grandmother's encouragement, Joukowsky grew up to become a prominent venture capitalist, activist and film producer. He continued to pursue his love for documentary filmmaking, getting advice from fellow Hampshire College grad and legendary director Ken Burns.

Today, Joukokowsky may have lost the use of his legs, but he's sitting on top of the world. He has completed his longtime dream of making a documentary feature about his grandparents, Defying the Nazis: The Sharps' War, co-directed by Burns, featuring Tom Hanks as the voice of Waitstill Sharp. The film will be aired on PBS on September 20.

Artemis Joukowsky, left, with Ken Burns in Los Angeles, CA, on July 28. Photo by PBS.

Originally created as a small documentary to be screened in churches and museums, Defying the Nazis has taken audiences by storm. Famed columnist Nicholas Kristof from the New York Times wrote about the film in his piece, "Would You Hide a Jew From the Nazis?" Joukowsky has spoken at a panel discussion at the White House which held a screening of his movie. At the discussion, Joukowsky spoke with the Deputy Secretary of State and Director National Security Advisor the White House, who underscored how important his film was in the context of today's refugee crisis — the biggest movement of refugees since the end of World War II.

"It's a dream come true," Joukowsky said joyfully during an interview with National Observer. "I feel like I've done what I promised."

The Sharps

During the Second World War, Martha and Waitstill Sharp were a young couple living in Wellesley, Massachusetts, with their son Hastings and infant daughter.

Waitstill and Martha Sharp. Photo from Defying the Nazis.

Waitstill was a minister of the Wellesly Hills Unitarian Church, educated at Harvard in law but drawn to social causes. Martha was a progressive social worker, educated with a full scholarship at Brown University, whose adoptive family had threw her out of the house when she insisted on continuing her studies rather than immediately entering the work force.

Both Martha and Waitstill were incensed at the war and persecution of Jews by the Nazis in Europe, to the point that Waitstill declared war on the Nazis from his pulpit.

Nazi supporters waving swastika flags to welcome Hitler. Still from Defying the Nazis.

Everything changed dramatically one evening in 1939 when Waitstill was reading by the fireplace and heard his phone ring. It was a recruitment call from the American Unitarian Association, asking if they could accept a mission to go to Prague and help Jews escape persecution from the Nazis. The Sharps weren't the first on the list to be called. By the time Waitstill picked up the phone, 17 other men had already been offered the mission, but all had turned it down. The couple hesitated but he and Martha decided to accept, leaving their two young children with trusted caregivers.

Joukowsky explains that the Unitarian faith drove them to put themselves in danger at a time when America was isolationist and not involved in the war in Europe.

"They had a strong sense of humanitarianism," Joukowsky said. "Most people view family and friends as the people to help first. If your mom calls, you drop everything and help her — but not necessarily if the call came from somebody in Somalia." But Martha and Waitstill viewed the problems of the persecuted Jews as their own cause, even though they were themselves not Jewish and lived far away from Nazi oppression and violence.

Once they went abroad to Czechoslovakia, the couple was given a crash course in how to write coded memos that couldn't be easily deciphered by enemies; how to identify and evade Nazi followers and spies, who were everywhere in Prague, how to destroy incriminating documents. Even after that, they still had to rely on their instincts. Waitstill and Martha both encountered terrifying, life-threatening situations that gave them only a minute or two to make choices that would save their lives, and those of the Jewish refugees they were accompanying.

Adolf Hitler. Screenshot from Defying the Nazis.

In one instance, Martha was on a mission to pick up a certain Czech dissident, only known as "Mr. X," and accompany him to safety. She suspected one of her drivers to be a Nazi agent, and had the car drop her off at a different location, to verify if he would come chasing her once she got out of the car (her instincts proved correct, and she barely escaped by hiding in an alley). Waitstill had to accompany Jewish intellectuals dressed as common tourists on a train, and faced the agonizing choice of whether to trust the messages of a stranger urging them to descend, or to ignore the message as a Nazi trap.

What's striking about their story was that after coming back from an exhausting and stressful first mission, the Unitarian Church asked them to go back for more missions as the war intensified and persecution of Jewish people turned increasingly horrific and sinister. Even though Martha initially refused, the couple nonetheless ended up returning repeatedly for the greater good, spending months apart from one another as one remained to watch the children and the other spouse went alone.

Waitstill's letters to Martha reveal an agonizing sense of loneliness, and fears that the couple was growing apart emotionally. Martha, especially, was transformed by the missions.

"No Jews Allowed" sign in German. Photo from Defying the Nazis.

Instead of going back to a quiet life, she made a run for public office in 1946. When the Israeli government wanted help from the U.S. to get tens of thousands of Jews out of Iraq in 1947, it was Martha who took the call and went solo to Baghdad on a mission that eventually got 124,000 Jewish people out of the country.

But despite the heavy toll the missions took on their marriage, resulting in its eventual collapse, and tension within the family, the Sharps never doubted they made the right call to accept the mission, he said.

One of the letters from Jewish refugees who Martha accompanied on a train through the heart of Nazi Germany wrote a note to her, which reads:

"Dear Ms. Sharp, we shall never forget what you have done for us and wish to thank you from the depth of our hearts."

Joukowsky said it made him extraordinarily proud when his whole family showed up to his film screening in Washington, and that they were inspired by the legacy left by the Sharps.

"When I was at the White House, every member of my family was there," Joukowsky said. "It was one of the most beautiful moments ever. My kids, their great grandchildren, were stepping up and saying: 'This is our credo. We're going to help other people as well.'"

Refugees today, and individual moral courage

Joukowsky hopes the film, and an upcoming book, will invite others to help refugees and those in need. What's striking about the film is its extraordinary parallels with the refugee crisis in the world today.

Then, as now, the U.S. was reluctant to accept refugees from wartorn countries, and the Sharps ended up struggling against their own country's government to expand its meager quota of accepting Jewish refugees from Europe. The film seems all the more relevant today when the major Republican presidential candidate is drumming up support for building a wall to block migrants, and to cut off all entry of Muslims, even refugees in dire circumstances.

"There was an enormous anti-immigrant sentiment," Holocaust scholar Deborah Dwork says in the film. "There was anti-Semitism and deep racism."

Jewish refugee children arriving in America, wearing beige berets given to them by Martha Sharp. The hats were to identify them on the boat. Still from Defying the Nazis.

Despite all the initial hostility, the Jewish orphans and families who managed to make it to the U.S. became full-fledged Americans, contributing enormously to American society. Joukowsky and Burns' film highlights that the efforts of thousands of brave individual citizens like the Sharps — not just government — were behind the lives that were saved.

A Jewish survivor who was saved as a child from the Nazis by the Sharps.

At one point in the film, a rescued Jewish writer asks Waitstill if he was being paid a large sum of money to help them. His response made it clear that they weren't taking these risks for money, or obligation to government, or even admiration from those he saved. He and Martha were simply doing what they believed was their duty.

With his film now complete, Joukowsky is publishing a book about the Sharps' work in Europe, based on their documents. After his grandmother passed away, he went into her basement and uncovered 14 boxes of documents, letters, photographs from the mission, as well as an unpublished memoir.

Today, Joukowsky is calling for people to share their own stories about moral courage from the public, to inspire others to act in in the interest of the common good. He's been moved to give an award to the former German chancellor Angela Merkel, who opened her country's doors to refugees, despite paying a heavy political price.

"This story, the movie, is really about how ordinary people can do extraordinary things. There is always a choice...What would the world look like if more people had moral courage?" he asks.

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