Dakota Fanning plays a woman with autism who writes a fan-fiction ‘Star Trek’ screenplay in a comic drama directed by Ben Lewin ('The Sessions').


The passion of the Trekkie meets the longing for self-sufficiency in Stand by Me, a wan road-trip drama revolving around a young woman who's on the autism spectrum. Helmer Ben Lewin, who located the intersection of acerbic irreverence and nuanced tenderness as writer-director of The Sessions, travels a far less satisfying middle ground with the new film. Working from Michael Golamco's adaptation of his own play, Lewin can't quite transcend the inconsistencies and dwindling credibility of the concept or give the material a driving pulse, even with its race-to-the-deadline setup.


But Dakota Fanning's understated performance roots the movie's flatly stated themes of self-realization, family and belonging in real-girl gumption. She plays Wendy, a group-home resident and Star Trek aficionado who's determined to enter a screenplay contest for fans that will commemorate the show's 50th anniversary. Beyond her love of the sci-fi franchise, she's convinced that the big prize will persuade her married big sister, Audrey (Alice Eve), that she's capable of returning to the family fold. In particular she longs to meet her infant niece — a step that Audrey has delayed because of Wendy’s history of violent tantrums. To realize her goal, Wendy becomes a sort of Alice in Dangerland, an innocent cast adrift on the highways and byways of California. But in this optimistic fairy-tale adventure, each danger she confronts is almost instantly matched by the rescuing act of a kind stranger.


In a panic over having missed the post office cutoff that would get her epic screenplay to Paramount Studios in time, Wendy sneaks out of her comfortable and loving group home in San Francisco. Crossing Market Street, let alone boarding a bus to Los Angeles, has long been forbidden to her.


With the guidance of the psychologist who runs the home, unflappable and bearing the Trek-friendly name Scottie (Toni Collette, reliably strong), Wendy lives by strict routine and structure. To ease the stress of decision-making, her wardrobe is color-coded by day (if it's Saturday, as it is when she hits the road, the sweater is red). Her job at a Cinnabon store is a good fit because it doesn't require eye contact with customers, something that would be a problem for her. Coworker Nemo (Tony Revolori) is a sympathetic soul who brings her mixtape discs, and, in a nicely played comic bit, mall-rat nerds challenge her deep Star Trek knowledge, to no avail.


With the unbound 429 pages of The Many and the Few in her backpack and her Chihuahua, Pete (an expressive pooch named Blaster who earns his reaction shots) in her shoulder bag, Wendy sets out on her life-changing journey. Her sister is soon in pursuit, as are Scottie and her teen son, Sam (River Alexander). Sam's apparent unhappiness and his friction with Scottie are pointedly introduced only to be abandoned with no further comment. Yet even with that story thread left dangling, Collette communicates plenty with her character’s powerfully wordless reaction to someone’s mention of their single mother.


Pete gets Wendy thrown off the bus near a fictional middle-of-nowhere Middleton City, where a retirement-village resident (Marla Gibbs) saves her from an unethical convenience-store clerk, only to unintentionally lead her into further harm’s way. By the time Wendy makes it to Los Angeles, there’s little in the way of believable incident to hold on to, as evidenced by Patton Oswalt’s portrayal of a cop — and not just a cop, but one who speaks Klingon.


Though the story falls flat, Fanning makes Wendy’s fixations and coping mechanisms persuasive and deeply felt, communicating her constant inner struggle in every gesture, whether she’s speed-knitting or anxiously calculating her next steps. The film’s title refers to a calming mantra that Scottie has taught her to use when sensory overload strikes. Authenticity on that front is bolstered by the casting of actors with autism as some of Wendy’s housemates, and the credits include an autism coach, Elaine Hall.


For the most part, Lewin (who explores a slice of World War II history in the upcoming Paul Rudd starrer The Catcher Was a Spy) uses a straightforward visual scheme. That gives the few subjective flourishes, blending Wendy’s surroundings with those of her imagination, more impact, as when the desolate part of a strange town transforms into an otherworldly desert.


Distributor: Magnolia Pictures
Production companies: Magnolia Pictures, 2929 Productions, Allegiance Theater Production
Cast: Dakota Fanning, Toni Collette, River Alexander, Patton Oswalt, Marla Gibbs, Michael Stahl-David, Jessica Rothe, Jacob Wysocki, Alice Eve, Robin Weigert, Tony Revolori
Director: Ben Lewin
Screenwriter: Michael Golamco
Based on the play by Michael Golamco
Producers: Daniel Dubiecki, Lara Alameddine
Executive producers: Ben Cosgrove, Todd Wagner, Tim Crane
Director of photography: Geoffrey Simpson
Production designer: John Collins
Costume designer: Annie Bloom
Editor: Lisa Bromwell
Composer: Rick Clark, Heitor Perreira
Casting director: Richard Hicks

Rated PG-13, 93 minutes