She was carrying apples, and decided to throw one over the fence. He caught it and ran away toward the barracks. And so it began.
As they tell it, they returned the following day and she tossed an apple again. And each day after that, for months, the routine continued. She threw, he caught, and both scurried away.
They never knew one another's name, never uttered a single word, so fearful they'd be spotted by a guard. Until one day he came to the fence and told her he wouldn't be back.
"I won't see you anymore," she said. "Right, right. Don't come around anymore," he answered.
And so their brief and innocent tryst came to an end. Or so they thought.
Before he was shipped off to a death camp, before the girl with the apples appeared, Herman Rosenblat's life had already changed forever.
His family had been forced from their home into a ghetto. His father fell ill with typhus. They smuggled a doctor in, but there was little he could do to help. The man knew what was coming. He summoned his youngest son. "If you ever get out of this war," Rosenblat remembers him saying, "don't carry a grudge in your heart and tolerate everybody."
Two days later, the father was dead. Herman was just 12.
The family was moved again, this time to a ghetto where he shared a single room with his mother, three brothers, uncle, aunt and four cousins. He and his brothers got working papers and he got a factory job painting stretchers for the Germans.
Eventually, the ghetto was dissolved. As the Poles were ushered out, two lines formed. In one, those with working papers, including Rosenblat and his brothers. In the other, everyone else, including the boys' mother.
Rosenblat went over to his mother. "I want to be with you," he cried. She spoke harshly to him and one of his brothers pulled him away. His heart was broken.
"I was destroyed," Rosenblat remembers. It was the last time he would ever see her.
It was in Schlieben, Germany, that Rosenblat and the girl he later called his angel would meet. Roma Radziki worked on a nearby farm and the boy caught her eye. And bringing him food - apples, mostly, but bread, too - became part of her routine.
"Every day," she says, "every day I went."
Rosenblat says he would secretly eat the apples and never mentioned a word of it to anyone else for fear word would spread and he'd be punished or even killed. When Rosenblat learned he would be moved again - this time to Theresienstadt, in what is now the Czech Republic - he told the girl he would not return.
Not long after, the Russians rolled in on a tank and liberated Rosenblat's camp. The war was over. She went to nursing school in Israel. He went to London and learned to be an electrician.
Their daily ritual faded from their minds.
"I forgot," she says.
"I forgot about her, too," he recalls.
Rosenblat eventually moved to New York. He was running a television repair shop when a friend phoned him one Sunday afternoon and said he wanted to fix him up with a girl. Rosenblat was unenthusiastic: He didn't like blind dates, he told his friend. He didn't know what she would look like. But finally, he relented.
It went well enough. She was Polish and easygoing. Conversation flowed, and eventually talk turned to their wartime experiences. Rosenblat recited the litany of camps he had been in, and Radziki's ears perked up. She had been in Schlieben, too, hiding from the Nazis.
She spoke of a boy she would visit, of the apples she would bring, how he was sent away.
And then, the words that would change their lives forever: "That was me," he said.
Rosenblat knew he could never leave this woman again. He proposed marriage that very night. She thought he was crazy. Two months later she said yes.
In 1958, they were married at a synagogue in the Bronx - a world away from their sorrows, more than a decade after they had thought they were separated forever.
It all seems too remarkable to be believed. Rosenblat insists it is all true.
Even after their engagement, the couple kept the story mostly to themselves, telling only those closest to them. Herman says it's because they met at a point in his life he'd rather forget. But eventually, he said, he felt the need to share it with others.
Now, the Rosenblats' story has inspired a children's book, "Angel Girl." And eventually, there are plans to turn it into a film, "The Flower of the Fence." Herman expects to publish his memoirs next year.
Michael Berenbaum, a distinguished Holocaust scholar who has authored a dozen books, has read Rosenblatt's memoir and sees no reason to question it.
"I wasn't born then so I can't say I was an eyewitness. But it's credible," Berenbaum said. "Crazier things have happened."
Herman is now 79, and Roma is three years his junior; they celebrated their 50th anniversary this summer. He often tells their story to Jewish and other groups.
He believes the lesson is the very one his father imparted.
"Not to hate and to love - that's what I am lecturing about," he said. "Not to hold a grudge and to tolerate everybody, to love people, to be tolerant of people, no matter who they are or what they are."
The anger of the death camps, Herman says, has gone away. He forgave. And his life has been filled with love.