I agree with those who say that there's more than simple imbalance in the fact that although around 60% of all translations are taken from the English language, English readers take only around 2-3% of their books from other languages. For a start, English readers must be missing out on hundreds of fine books every year and the figures also provide a troubling indication of cultural imperialism and the narrow horizons of US and UK readers.

Even so, I understand that it's easy to be lazy. There are so many novels published in English already, so many perfectly decent English language novels rejected every week, that it's easy to ignore what's going on elsewhere. The tyranny of my to-read pile makes the prospect of millions more books just waiting to be made accessible as terrifying as it is exhilarating. Since tutting over the last flurry of articles about English literary parochialism last December and agreeing that something ought to be done, I have managed to read exactly zero non-English or translated books.

But all that changed last week, when I was persuaded to look at the new Penguin translation of Alone In Berlin by Hans Fallada – and reminded that although it's easy to be lazy, it's worth putting in the effort.

The fact that this book was first published in Germany in 1947 and has only appeared now in English is good demonstration of how much catching up we have to do. Especially since it is both a cracking read and a vital historical document – one that Primo Levi called "the greatest book ever written about German resistance to the Nazis".

It's a fictionalised retelling of the story of Otto and Elise Hampel, an elderly working-class couple who spent more than two years dropping postcards around buildings in Berlin denouncing Hitler's rule. The hope was that those who picked them up would be motivated to resist the Nazis too, but most people just handed the cards into the police. Inevitably, the couple were arrested in October 1942. After a show trial, they were beheaded.

Fortunately, their heroism didn't go entirely unnoticed. After the war, the Gestapo files relating to their case were handed to Fallada by Johannes Becher, a culture official in East Germany, who hoped this already successful and prolific writer could turn something worthwhile around quickly. Fallada far outstripped his expectations. He is said to have produced the 500 pages of Alone In Berlin in less than a month – while struggling with morphine addiction.

Unsurprisingly (at least if that rapid turnaround story is to be believed) the novel has a few rough edges – but not enough to detract from its overall power. It's a gripping dark thriller, and the knowledge that the couple are doomed only adds tension to the game of cat and mouse the Gestapo play with them. But, of course, it's a detective story gone wrong. The criminals here are not the people the police are hunting, but the police themselves. Fallada exploits this cruel irony to the full, with a devastating depiction of what happens to "justice" when it is controlled by lawless murderers. Equally impressive is his evocation of life near the bottom of the ladder in wartime Berlin: of hardships and degradations endured, of people disappearing without explanation, and of the near constant threat of violence. Evil times that leave hardly anyone unscathed or untainted.

It's Otto and his wife's determination to "stay decent" that sets them on their dangerous course – and it's here that the book really resonates. Fallada's portrait of these people who "didn't participate" is moving. It can only be supposed that much of this emotional weight was born of hard experience. Although far from being a Nazi, the writer had to make all kinds of compromises to survive (he even agreed to write an anti-Jewish book for Goebbels and only avoided doing so by entering a lunatic asylum). He was nowhere near as spotless of the heroes he so admires, but that helped deepen his empathy. As such, this exploration of what it means to be innocent (like its two great contrasting explorations of guilt, The Tin Drum and Doctor Faustus) could only have been written by a German who had lived through the Nazi regime.

In other words, it's an important book that no English writer could have written – and so another resounding argument for the importance of taking in translations. It makes me wonder what else we've been missing.