Justin Schwarz's debut follows a family retracing the path of the Lewis and Clark expedition.

THE HAMPTONS, NEW YORK — The past is never history in Justin Schwarz's The Discoverers, a family-reconciliation tale in which three generations of estranged relatives are forced to stick together on a historical reenactment of the Lewis and Clark expedition. More warm-hearted than funny, Schwarz's feature debut benefits from an intelligent script and sympathetic lead performance by Griffin Dunne, though commercial prospects are modest.

Dunne plays Lewis Birch, a history prof whose career is foundering thanks to his inability to complete a mammoth book about York, a slave who belonged to William Clark on the 19th-century expedition to the Pacific coast. His revisionist fixation on that trek traces to his youth, when Lewis's stern father Stanley (Stuart Margolin) forced the family to annually recreate it: Years later, Lewis's parents still don period garb and join fellow history buffs for a musket-and-axe trek westward.

When Lewis's mother dies, leaving Stanley almost catatonic, Lewis is forced to engage with the father he stopped talking to many years ago. Interrupting a trip to an academic conference where he had hoped both to revive his career and reconnect with his own teenaged kids (who, post-divorce, live with their mom), Lewis reluctantly takes both his kids and his dad into the woods.

The community of reenactment enthusiasts they meet is shown in a predictably goofy light -- David Rasche's Cyrus gets flustered whenever his new companions use 20th century language or, Heaven forfend, hide a cell phone inside their buckskin trousers -- but they aren't all nut-jobs. Cara Buono's Nell, a helpful blonde who'd be a love interest if Lewis were less hapless, is quietly accommodating when one of the kids turns out to be vegan or another gets busted with a stash of weed.

Lewis's children (played by Madeleine Martin and Devon Graye) are less well drawn than they might have been, serving more often than not as a source of mildly sullen complaint; but Martin's Zoe has a bright spot when an emergency requires her and her father to take a secret detour into the modern world. The academic-conference subplot, in which Lewis keeps sneaking off for phone calls attempting to salvage his appearance, sometimes feels like a contrived difficulty; as the story progresses, though, the subject of Lewis's life's work is nicely woven into the drama, lending some intrigue to a father/son grudge that would otherwise be generic.

Production Company: Quadratic Media

Cast: Griffin Dunne, Madeleine Martin, Devon Graye, Stuart Margolin, David Rasche, Dreama Walker, Ann Dowd, Cara Buono, Becky Ann Baker, Scott Adsit, John C. McGinley

Director-Screenwriter: Justin Schwarz

Producers: Justin Schwarz, Laura Kleger, Louise Lovegrove

Executive producer: Bob Gosse

Director of photography: Chris Blauvelt

Production designer: Kelly McGehee

Music: Aaron Mirman

Costume designer: Kim Wilcox

Editor: Geraud Brisson

No rating, 104 minutes