Peter Heller's string of gripping adventures gets darker and a bit more political in his latest, "Burn."

Fans of Leif Enger's "I Cheerfully Refuse," released last spring, will recognize the territory.

Unspecified events, springing from the political divide in the U.S., have the country breaking down, on the edge of apocalypse. A decent man (in the case of "Burn," two decent men) roams from one perilous situation to the next, all the while protecting a young girl he met while on a search for someplace safe. It's bleak but Enger and Heller hold out hope that humans can figure out how to meet in the middle before the world burns up.

Heller's "The River," "The Guide" and "The Last Ranger" were page-turning novels, with evocative portraits of men in nature, fighting other men who don't understand the gift that the outdoors represents. There's a strong sense of time running out — because of climate crisis and human stupidity — but "Burn" leans harder on the stupidity part of that equation. The result is that "Burn" occasionally feels more didactic than Heller at his lean, spare best.

There haven't been many children in Heller's books and I'm not sure "Burn" benefits from the presence of Collie. She's a frightened girl who complicates friends Jess and Storey's struggle to survive on a Maine hunting trip that bumps up against a well-armed militia, bent on overthrowing the government. I'm also not sure what to make of jarring flashbacks to adolescence that connect Jess and Storey in a surprising, but not especially illuminating, way.

Those are minor flaws, though. Because "Burn" grabs you from its first chapter — in which Jess and Storey wander into an abandoned town where the torched buildings are still smoldering — and never lets go. Heller doesn't provide many signs that his warring factions can come to an understanding but, as in all of his books, he offers comfort in the goodness of (some) people and the very human instinct to keep each other safe.

Burn

By: Peter Heller.

Publisher: Knopf, 290 pages, $28.