NEW YORK–In 1941, a poor Polish farmwoman travelled from the countryside to Israel Rubinek's village store, but found she didn't have enough money to pay for the things she needed.

Rubinek, a gregarious 21-year-old who sold kerosene, soap and shoelaces, told Zofia Banya not to worry: They'd settle up the next time she came to Pinczow, in German-occupied Poland, to sell butter and eggs.

It was wartime and hardly anyone offered credit. Who knew what life would be like a day later, let alone a week?

Rubinek's kindness set off a series of life-changing events that would ripple through his family for generations. In 1943, when Jews were being executed or rounded up into concentration camps, Banya sent word through a friend asking him and his young wife Frania to come to her farm.

The Catholic woman had little to offer, but she could hide them. Her gesture was fraught with peril. People could be shot for harbouring Jews. But together the two couples might be able to save each other – the Rubineks had access to a little money – and endure the war.

"I felt so much pity for them it was impossible to betray them," Banya says in the documentary So Many Miracles, made by the Rubineks' only child, Saul, a Canadian actor and director.

She sheltered the Rubineks for almost 2 1/2 years.

In 1986, Saul returned to Poland with his parents, who were going back for the first time in 40 years, to meet Banya. Saul documented their emotional reunion in the film and in a book of the same title.

Saul tells this story in the Manhattan apartment, where he lives with his producer wife, Elinor Reid, and children Hannah, 18, and Sam, 14. Saul was born in a displaced persons' camp in Germany in 1948, came to Montreal as an infant and later lived in Ottawa and Toronto. One of the stars of the Syfy network series Warehouse 13, he recently moved from Los Angeles to be closer to Hannah's university and Toronto, where the series is filmed.

Saul has been in dozens of television series and movies, and will appear in the forthcoming adaptation of the Mordecai Richler novel Barney's Version.

His parents' story and kindness are pivotal to him, he says. "Selfless acts, gratuitous acts of kindness – they are important in everyday life, to make life bearable."

But Saul's view of kindness is not sentimental – it's sharp and challenging, as is conversation with him in his comfortable apartment. It's a place of work and strong family bonds. Laptops on the big dining table. The smell of cinnamon and cloves coming from the kitchen. Sam welcomed home from school; Hannah about to arrive from university at Grand Central for the Thanksgiving holiday.

Saul was spurred to make the film and book versions of So Many Miracles because he couldn't understand his father's intractable opposition to his youthful relationship with a girl who wasn't Jewish. Nor did he fully understand his parents and the nightmares that made them wake in the night screaming. He hoped by interviewing them he'd learn about their lives and his own place in family history.

"Of course my parents' lives were saved because of the kindness of this woman," says Saul, 62. "But I think it's too small a word. I think it's something we ascribe to someone opening a door – maybe that's just being polite. This was huge. They risked their lives to save my parents."

There were complications in Zofia's offer of sanctuary. Her husband, Ludwig, opposed harbouring the Rubineks. When they stepped off the wagon that brought them to the Banyas' farm, Zofia, who was about 10 years older, welcomed them as if they were her own children, but Ludwig was stone-faced. He was a fierce anti-Semite and a sadistic spouse, not above kicking his wife with his heavy boot. He told the Rubineks, "A Jew is nothing. Everybody can kill them."

There was another problem: Frania was pregnant. It was dangerous but still possible to hide two young people in the Banyas' farmhouse. The four adults shared one whitewashed, dirt-floored room with Zofia's 7-year-old son Maniek; the other half of the house was a stable. But a crying baby could alert passersby less sympathetic than Zofia and more than willing to betray their neighbours.

Saul Rubinek is circumspect in his book and film about the baby girl Frania delivered. Zofia took the baby away. The baby died. While his parents and Zofia were alive, he never revealed what he and his family believed was the baby's fate.

"It was pretty clear she killed the baby," Rubinek says now.

"What else would have happened? My mom was absolutely sure. My parents didn't blame her ... they believed a crying baby meant they were all going to die.

"Everyone was very practical – but it's horrific, too. There are deep ironies. When you say the woman who saved my parents' life also killed my sister – it was not out of malice. My parents' lives, our lives – I wouldn't have been here if she hadn't taken my parents in and fought her own husband to make sure they were okay. She was very down to earth. She would have had to be to survive."

Something deeper evolved as the Banyas and Rubineks lived together. "There was affection. When Zofia got to know them better, there was a deeper connection. And she couldn't kick them out, even when the money ran out."

Loading... Loading... Loading... Loading... Loading... Loading...

Frania's sister, who lived in Warsaw posing as a Gentile, made sure they got money, which they shared with the Banyas. But that ended when she was conscripted to work in a German munitions factory.

Despite their poverty and Ludwig's threats, the Banyas hid the Rubineks for 28 months. "My husband wanted to throw them out – he beat me a lot," Zofia says in the documentary. "I knew we couldn't. It would be on my conscience all my life if they met their deaths because of us."

There was a little crawl space dug out beneath the woodstove where the Rubineks hid when neighbours or authorities came. German soldiers commandeered the room one night and slept inches away from the terrified Rubineks. Israel had a cough that he could not suppress. Young Maniek, who says in the documentary that even as a child he felt a moral duty to safeguard the couple, was resourceful: he purposely coughed and tossed restlessly through the night so the soldiers wouldn't hear Israel.

Rubinek observes that the German manufacturer Oskar Schindler, who rescued 1,200 of his Jewish factory workers, was powerful and well-educated – a man with the time and wherewithal to change his thinking. "But somebody like Ludwig? It was as natural for Ludwig to be anti-Semitic as to be from Toronto and a Blue Jays fan. It was normal, it was everybody. Jews were apart, they were the other. There's something deeply heroic about someone much more ordinary, a profoundly powerless person who is torn about his feelings about Jews."

After they moved to Montreal, Saul and his parents didn't forgo lessons from the war. From the moment they arrived and until they died – Israel in 1996, Frania in 2000 – Israel and Frania regularly sent Zofia money.

"I was raised to be kind," Saul says. "My parents were underdogs. Immigrant Jews. I spoke with an accent. I didn't speak English even – I spoke French and Yiddish mostly. I was picked on. They threw stones at me and called me Dirty Jew, Christ killer, maudit Juif.

"My parents taught me the way to deal with being picked on was to be compassionate. I had to defend myself physically, but I had to be compassionate and understand the position of those abusing me. I had to figure it out and then rise above it."

Israel and Frania's story resonates for the young generation of Rubineks. Saul's daughter Hannah, a thoughtful and articulate drama student, has ruminated on the complex nature of the kindness shown to her grandparents.

"It's usually correlated with something as benign as being nice," Hannah says. "It's not simple. Zofia Banya hid my grandparents, but she killed my aunt."

She wonders what the outcome would have been had that child lived. Would her grandparents have survived? Would she even exist?

One of Hannah's closest pals is a descendant of an SS officer who operated in the same part of Poland where her grandparents were. "It fits in with my dad's view of interconnectedness. It's extraordinary that two or three generations later, I'm best friends with that girl."

One day, Hannah encountered her friend outside of class. "She was crying and said, 'Everyone has great, heroic stories from World War II and I have this horrific one.' And I said, 'But that's not you. All we can do is learn from what happened and be aware so it doesn't happen again.' "

Hannah takes great hope from the story of her grandparents. "That one act of impossible kindness in that impossible situation affected everything," she says. "The depth of the soul's capacity is immeasurable and unfathomable. These poor Polish farmers were terrified for their lives, yet they take these two people in they barely knew.

"Yes, it happened, and it's stopped me from despairing of the world. If that can happen, anything can."