At first glance, Diane Ackerman’s The Zookeeper’s Wife seems quite a departure from her other books, such as the best-selling A Natural History of the Senses. A tireless researcher, Ackerman is nonetheless a writer who luxuriates in sensory exploration and metaphor — making her a less-than-obvious choice to tackle a true story of the Second World War. It’s a tribute to her talents that the book feels both triumphant and inevitable by the last page.

In pre-war Warsaw, Antonina Żabiński and her husband Jan ran a zoo housing rare animals, many of them raised by hand by Antonina, who had a rare gift for connecting with the creatures in her care. Many animals roamed the zoo grounds freely or loped through the villa she and Jan shared. The Żabińskis’ was a world preoccupied by zoo births, deaths, and arrivals.

When war broke out, however, a German zookeeper seized the Żabińskis’ valuable animals. Not only did the ideology of the Third Reich demand the creation of human racial purity — an Aryan race spilling over into the lebensraum or “living space” created by the deaths of millions of Jews, Gypsies, and ultimately Slavs and other races — but also an animal purity. Architects of the Reich theorized that by “back-breeding” — breeding animals with the most visible archaic traits — extinct animals such as tarpans (wild horses) and aurochs (cattle) could be recreated. Thus conquered zoos saw their animals shipped off for display and breeding experiments.

In Warsaw, Poland’s surrender meant the single-minded persecution of the Jewish population, but in emptying the zoo, the Nazis unwittingly created a sanctuary in the center of the city. “In the summer of 1940, a phone call, a note, or a whisper might alert the Żabińskis to expect secret ‘Guests’ placed by the Underground,” writes Ackerman. Some guests stayed in the zoo’s villa and some in the emptied cages. Ackerman shows how critical the couple’s keen sense of predator-prey relationships became at this stage: “In the wild, animals inherit clever tricks of blending into their surroundings. … The best camouflage for people is more people, so the Żabińskis invited a stream of legal visitors — uncles, aunts, cousins, and friends for varying stays — and established a regular unpredictability.”

Tense with the threat of discovery at a time and place when giving a Jew water was punishable by death, the zoo under the Żabińskis nonetheless remained a place alive. Unlike the depressing bunkers where many Jews hid, Antonina wrote in her diary that “the atmosphere in our house was quite pleasant . . . sometimes even almost happy,” with music in the evenings, the few animals the family could continue to keep, and, mostly, Antonina herself, a woman who served sit-down meals, analyzed in her diaries the emotional needs of her guests, and refused to lose her sense of connection to the world. In spite of the carnage around them, the Żabińskis saved the lives of approximately three hundred Polish Jews — ironically, in a space created partially by the German drive toward eugenics.

It would have been tempting in a tale like this to reach for the obvious metaphor of Jews animalized, hiding in cages from Nazi persecutors. The truth is far more complex than that: Antonina, who eyed two terrified lynx kits and understood how to coax them into security, emerges as the opposite of all the Nazis bring with them to Warsaw. Throughout the war she remains empathic, intuitive, able to allow the natural and human world to proceed as it will — able to give, apparently with little discussion, her own lebensraum to allow others to survive. Ackerman, with her profound understanding of nature, tells Antonina’s story in a way that makes it clear her roles as the zookeeper’s wife and heroine of the Resistance are inextricably connected, both in what the natural world has taught her, and taught her to accept.