One day last March, former U.S. Sen. Rudy Boschwitz opened his Wall Street Journal to find a review of a book that had been written by his cousin Ulrich. His cousin, who he hadn't known was a writer. His cousin, who had died in 1942.

"I was startled when it appeared," Rudy said. "I had never heard that Ulrich was a writer."

Ulrich Alexander Boschwitz turned 15 in 1930, the year that Rudy was born. Their fathers were brothers — Rudy's father, Ely (pronounced Eli), was the fourth of five brothers, and Ulrich's father, Sally (pronounced Zelly), was the youngest. The two families lived in the same Berlin apartment building, on different floors.

"I must have met Ulrich — he must have been up in our apartment" at times, Rudy said. But he didn't remember him. Ely took his family out of Germany in 1933, when Rudy was just 2; "I have no recollection of Germany at all."

Ulrich left Germany two years later, in 1935. Like Rudy's family, and like the protagonist of his novel, "The Passenger," Ulrich had a peripatetic existence for the next few years as he tried to find a permanent home in a world on the brink of war.

Rudy's family traveled from Berlin to Czechoslovakia to Switzerland to Amsterdam to England before finding an American consul who would grant them a visa to emigrate to the United States, which they did in December 1935.

Ulrich moved from Germany to Scandinavia, Paris, Belgium, Luxembourg and finally England. When the war broke out, England declared him an "enemy alien." He was first interned on the Isle of Man and then deported to Australia.

While still in England, Ulrich wrote "The Passenger" — a Kafkaesque novel about a German Jewish man on the run — quickly, over four weeks, after the horrific events of Kristallnacht in November 1938. The novel was published, but soon fell into obscurity.

Following the attack on Pearl Harbor, Ulrich's status changed to "friendly alien," and he set sail for England once again aboard the passenger ship the Abosso.

He had planned to revise the novel, but on Oct. 29, 1942, the Abosso was torpedoed by the Germans. Three hundred sixty-two passengers perished; 31 survived, but Ulrich was not among them. He died at age 27.

In 2015, the manuscript of "The Passenger" was rediscovered in a German archive. Publisher Peter Graf, who specializes in reviving forgotten or neglected books, edited it and published it in Germany in 2018.

It has since been published in 80 languages, including English, and became a bestseller in England.

Set in 1938, "The Passenger" centers on a German Jewish businessman and World War I veteran, Otto Silbermann. As Jewish businesses are confiscated, properties seized or turned over to Gentiles, and Jewish people are rounded up, Silbermann has a great deal of trouble coming to terms with what is going on in his country.

"Tomorrow the government might well declare it all happened without their knowledge," he tells himself. "Even if it is full of anti-Semites, it is still the government, and this is something they simply can't allow."

But as the novel progresses, the truth becomes clear.

With Nazi stormtroopers pounding on his front door, Silbermann slips out the back and goes on the run. And for the rest of the novel, he is on the lam, moving from train to train and city to city in a frantic effort to elude the Nazis and stay alive.

"Is it going to go on like this forever?" Silbermann wonders at one point. "The traveling, the waiting, the running away?"

The book garnered reviews in the Wall Street Journal and the New York Times and was named one of the best books of 2021 by the Star Tribune, the Times of London, the Financial Times, the Guardian and elsewhere.

It's an important book, Graf said in an interview with an online journal, partly because of when it was written — at the very time the pogroms were taking place. Publishers Weekly called it a "chilling time capsule" which "offers a startling image of fascism taken hold."

After seeing the Wall Street Journal review, Rudy Boschwitz was given a copy of his cousin's novel. But he hasn't read it.

"I don't read books about the treatment of the Jews," he said. "Of our family that didn't leave the continent of Europe — there were a number in Poland — they were all killed but one. I don't read much about that time."

That doesn't mean he doesn't care — just the opposite.

"I was one of the senators who got the land for the Holocaust Museum in Washington, D.C.," he said. "But I never went through it. I just thought I couldn't."

Still, the discovery of the book has been poignant for him. "I realized I had a very talented cousin that I was sorry I never knew."

The Passenger

By: Ulrich Alexander Boschwitz, translated by Philip Boehm.

Publisher: Metropolitan Books, 288 pages, $24.99.