‘Night Moves:’ Fine film about a dam fool notion

Has an act of eco-terrorism ever changed a single person’s mind about the environment? The wheels of justice grind in the usual ways; the bomber or arsonist goes about his business feeling righteous, before and after; the average person raises an indifferent eyebrow, complains if the event inconveniences him and goes back to despoiling the planet in a hundred small ways.

Kelly Reichardt, who directed “Night Moves” and wrote the script with Jon Raymond, asks that question in this quietly unsettling movie. The plot could hardly be simpler: Three people in Oregon, two brothers and a rich girl bankrolling their operation, decide to blow up a dam that’s preventing salmon from spawning. The consequences aren’t simple at all.

Josh (Jesse Eisenberg) works on a collective farm, where fellow vegetable growers have only a faint idea of his extremist plans. He has somehow paired up with Dena (Dakota Fanning) and takes her to meet Harmon (Peter Sarsgaard), an ex-Marine who understands explosives. From the start, the operation becomes more complicated than expected, until it climaxes in an event no one foresaw.

Reichardt and Raymond remain unusually objective. We can find Josh and Dena’s aims idealistic but their methods inappropriate; he’s humorless yet compassionate, while she’s knowledgeable about the damage we’re doing to nature yet naive. (Harmon’s pretty much a reclusive loser; he complains about golf courses usurping precious fresh water while working at one.)

Whether or not we approve of their actions, a farmer observes that the river contains many dams; they’d all have to come down for fish to flourish. If Dena’s right in believing the planet will be irredeemably ruined before the end of the century – a view some scientists now hold – does an improvement on one stretch of river even matter?

All three leads give effective, low-key performances. (I don’t remember a single character raising a voice.) Their acting fits the tone of this movie and all the ones Reichardt directs: Her camera moves slowly, and she accumulates tension by showing detail after detail. We see the telltale mud on Josh’s boots after the detonation; will the cop questioning him see it, too?

En route to the explosion, the three drive through a recreational area where tourists sit in massive RVs, watching “The Price is Right” on TV; later, they float past stands of topped or clear-cut trees. Nobody comments, but the implications are clear.

The film ends quietly, at precisely the right place. We’re on the brink of a new story, with one character seeking a new direction. Yet the feeling we’ve had through the whole film suddenly intensifies: Certain choices in life can never be run from, repented or repaired.