Kelly Reichardt’s Wendy and Lucy is a minimalist, modern-day The Grapes of Wrath — a nervous study of nomadic hardship with impeccably scouted locations, atmospheric sound design and a script built on the internalized distress of destitution.

Even over this 2008 drama’s many silent passages, Michelle Williams dazzles with a dressed-down performance in which her trademark locks are snipped, dyed and ratty.

It’s left to speculation why Wendy is running, but she’s departed from Indiana with dog Lucy in tow, her destination an Alaska fish cannery. When Wendy’s car stalls in Oregon, it strains her meager budget, but she’s no noble cipher unfairly thrust into poverty.

Sympathetic but flawed, Wendy quickly reaches at a lure desperation dangles in front of her — stealing groceries, getting arrested and losing Lucy. (As much of a blowhard as John Robinson’s clerk is about Wendy’s thievery, deep down she knows he’s in the right.)

This is the downbeat, dejected truth of pure pennilessness — the opposite of Chris McCandless’s willful disconnection from the grid in Into the Wild.

Dilapidated homes and depressed people surround Lucy, but so does unexpected compassion and altruism from a friendly security guard (Walter Dalton). The only misstep comes from Will Patton’s mechanic, unnecessarily affecting tics.

Avoiding political grandstanding, Reichardt leaves blame for American indigence to someone else — simply presenting a hard-times hierarchy that could undo Wendy.

The film ends on a devastating farewell, but also imparts important empathy to Wendy: Although she’s at the bottom of the barrel, there are those still inescapably trapped beneath its weight.