Delve into anyone’s family history and you’ll find stories. But there aren’t many families like Hadley Freeman’s where the narrative of her grandmother and her brothers feels as though it was carefully crafted to show the fate of Jews in the twentieth century. With high drama, heart-breaking tragedy, thwarted love and walk-on parts for Pablo Picasso, Marc Chagall and Christian Dior, Freeman’s memoir House of Glass would feel too neat if it were a novel. It certainly reads like one, and if I were a film director I’d be snapping up the rights.

The book starts with Freeman’s discovery of a dusty shoebox in her late grandmother’s closet, hidden behind a pile of leather handbags. The contents included a sketch by Picasso, a metal plate with a prisoner’s name and number written on it, pages from a book entitled Dressmakers of France and a picture of her grandmother as a young woman, embracing a man. His face had been scratched off by someone’s fingernail — “presumably my grandmother’s,” writes Freeman.

The discovery actually came six years into Freeman’s quest to find out more about her father’s family history, and her research took another 12 years, and went far beyond just family. But the find convinced her to focus on the siblings, her grandmother Sala and great uncles Henri, Jacques and Alex. They started out with the surname Glahs, changed it to Glass in Paris and Alex adopted the name Maguy when he became a fashion designer. Each has a fascinating story to tell, pieced together from left behind artefacts, official records, and Alex’s case, a lively account of his life, including a leap from a train taking him to Auschwitz, doubly death-defying,

“I’m not saying my family is a microcosm of the Jewish experience,” says Freeman when we meet, “but it felt like it covered a lot of 20th century bases .”

We’re in the foyer of Kings Place, where the Guardian has its offices, the paper she has worked for ever since leaving university. It’s also the venue for Jewish Book Week, which takes place next week. She’s not speaking during the week itself but is doing a JBW event on March 16 in conversation with fellow Guardian (and JC) columnist Jonathan Freedland. Freeman also used to write a column for this paper.

Today she’s been let down by her babysitter so she’s accompanied by baby Betty, eight months old, who behaves beautifully throughout. Freeman also has four-year-old twin sons, she works full time as a feature writer for the Guardian and has written several other books . That she has carved out the time to research and write this book is immensely impressive.

She started out as a fashion journalist and today, she looks quirkily great in a Zara gold skirt and a Christmassy jumper; bare legs and ankle boots It’s a very different look from her grandmother Sala’s distinctly French style “Yves St Laurent-like peasant tops, Chanel-esque jackets, proudly emphasising her non-Americanness through her clothes,” writes Freeman. She remembers her grandmother as melancholy, having constant arguments with her husband.

It was only through her research that she understood why.

The siblings were born in Poland, but fled to France after pogroms in their home town of Chrzanow. Alex describes it in his memoir: “a savage screaming crowd that seemed like a monster. They were attacking animals, wild beasts from the guts of hell. From their distorted snouts came cries of terrible hatred which I found impossible to understand.”

In Paris, three of the siblings embraced new opportunities, especially the art and beauty around them. Only one sibling Jakob —renamed Jacques — clung to the past, as did their mother. They stayed within their community of Polish Jews and failed to grasp the threat of the Nazis when they arrived.

The seeming passivity of Jacques, and his eventual fate, is very hard to read about. It was his name on the prisoner’s metal plate in the shoe box, and he who failed — it is the only word — to protect himself against murder. He even escaped from a Nazi prison, only to return out of solidarity with his bunkmates.

“The story of Jacques is so tragic and extraordinary,” muses Freeman, “and when he went back, it wasn’t a stupid thing in his mind.” She puts it down to trust. “He believed that if he followed the rules he would be alright.”

Jacques’ brothers were cannier and survived the war, through chance and cunning and sheer luck. The oldest brother, tall handsome Henri —born Jehuda — stayed in Paris in hiding with his wife Sonia, who had to make regular visits back to their apartment to destroy the letters left by their neighbours denouncing them to the authorities.

Freeman knew little of her great-uncle’s business before her research, but discovered that he invented a way of copying documents onto microfilm — cutting edge technology at the time. In wartime, he microfilmed the archives of countless businesses, museums and small towns, saving the records from destruction, After the war, his firm had the job of microfilming the concentration camp archives in Germany and Poland, keeping the names alive of millions who had perished, including his own brother Jacques.

Alex’s story is even more extraordinary, and Freeman had to work hard to sift fact from fiction. He was the youngest and boldest of the brothers, who hung out with artists and jazz musicians — “he put himself at the absolute centre of the city’s artistic and bohemian demi-mode”. He was never going to be a jobbing tailor like his brother Jacques, he set himself up as a couturier and succeeded by sheer determination, and chutzpah — and a draughtsman named Christian Dior.

He saw clearly the danger the Nazis posed to his family, and joined the Foreign Legion to try and get citizenship. There he made contacts in the French army that would later save his life. His life could have been devised by a thriller-writer, and I’m loath to give away too many spoilers, but his personality crackles off the page. The story of his escape from the train to Auschwitz — and Freeman’s detective work to track down the truth of what happened next — are riveting.

Alex’s swagger and dramas are a sharp contrast to Freeman’s grandmother Sala, the only sister. She spent long spells in sanatoriums as a teenager suffering from pleurisy, and once cured fell in love with the elegrance and beauty of Paris. She was in love too with a young man, a dental student.

But the war was approaching, and her brother Alex met an American man visiting Paris, whom he invited for dinner with the family. The man — Bill Freeman — fell in love with Sala. Alex persuaded her that she must accept his proposal, that by going to America she could save herself and possibly the rest of her family. So she sailed to New York to marry a man she hardly knew.

“She didn’t see it as this amazing sacrifice,” says Freeman. “It was more, of course she did that. What else would you do? Of course you’ll push off and marry some random man you barely knew.”

Freeman sees much resonance in her family’s story and the current situation for Jews. She calls out antisemitism when she sees it, including at the Guardian.

She acknowleges that many Jews have been less than impressed by the paper’s coverage of politics but insists: “I’m very proud to work at the Guardian. It’s very much a broad church and I’m lucky to have editors who let me write what I want on this subject.

I’ve written quite a lot about antisemitism and I have lots of like-minded friends in the building and of course there are people who disagree.”

One of the many fascinating aspects of the book is that several of the next generation were drawn to the world of fashion. One cousin organises fashion shows for many leading French designers, including Dior. He had no idea of his family connection with the designer until Freeman uncovered it.

The book took 18 years to research and 18 months to write. A week away from publication on March 5 it has been acclaimed by everyone from Salman Rushdie to Nigella Lawson. “It is a brave and wonderful book’,” said the American author Nathan Englander. So, what next? She’s signed a two book deal and is nervous. “I feel like I should just write one of those books people read on the toilet, like a day in the life of my dog or something, to make it really easy. Something that ideally won’t require 20 years of my life.”

She might even try fiction this time. “ I don’t know, because I feel I need non-fiction like a crutch, but I’m so impressed with people whon write fiction.” She loves writers such as Melissa Banks who write about contemporary Jewish life.

“There’s only so many of us Jews around, but when you read a book that really relates to your experience, it’s a wonderful feeling.”

House of Glass: The story and secrets of a twentieth-century Jewish family is published by Fourth Estate. Hadley Freeman is speaking at Jewish Book Week on March 16.