You might sigh at the thought of yet another drama about Jews hiding out from Nazis during World War II, but “No Place on Earth,” an extraordinary combination of documentary and dramatization, proves that even well-trod territory can be traversed in innovative ways. And this time, unlike in “Schindler’s List” or even Agnieszka Holland’s recent “In Darkness,” which had an uncannily similar plot line about an underground hiding-place, a gentile isn’t the hero. Instead it’s the family matriarch, Esther Stermer, who’s the guiding force here.

Janet Tobias begins her film with Christopher Nicola, a garrulous American spelunker who travels the world investigating caves as a hobby. In 1993 he undertook an expedition to some famous caverns in Ukraine, in the course of which he discovered what appeared to be signs of past human habitation. Determined to discover who might once have lived in them, Nicola talked to locals but found them close-lipped in the wake of years of Soviet repression. In time, however, some suggested that Jews might have hidden from the Nazis there during the war, and eventually Nicola was able to track down the survivors of the families that took refuge there in 1942 and remained—with a move from one cave to another after the first was discovered by the Germans—for over five hundred days until the liberation of the area by the Soviet army.

Tobias narrates the experiences of the Stermer and Wexler families through an unusual mixture of documentary and recreation. Actors portray the members of the clan, but their scenes are intermingled with recollections by Saul and Sam Stermer and Sima and Sonia Dodyk, whose words are often backed by archival material like still photos which blend into the reenactments. And at the close the elderly survivors are brought back to the caves to revisit the places where they had spent so much of their young lives.

“No Place on Earth” is effective as a dramatization of the families’ plight, filled with episodes that are exciting and suspenseful in their own right. They’re not overdone, however, instead being presented in a straightforward, matter-of-fact style that neither overplays nor underplays; this is by no means a sensationalized account, much of it shown in appropriately dark, shadowy images. And the emotional impact is enhanced by the testimony of the survivors, whose recollections are similarly quite direct but carry a strong impact.

The result is a Holocaust film that’s also a modern detective story, one with enough twists to make it fascinating and a conclusion that exudes real emotional power. Against a backdrop of villainy it shows us some honest past heroes—flawed, to be sure, but real—as well as an admirable, and engaging, modern adventurer of sorts in Nicola. Tobias deserves thanks for telling the story of them all in such a satisfying way.