Hans Christian Andersen meets “Green Acres” in helmer Marilyn Agrelo’s “An Invisible Sign.” Based on the popular Aimee Bender novel “An Invisible Sign of My Own,” pic is an offbeat fable in which Jessica Alba steps out of her comfort zone, and obsessive-compulsive disorder gets thrust front and center. Alba and other cast names including J.K. Simmons, Chris Messina and Sonia Braga should generate interest in a purposefully quirky film that auds will find offhandedly charming, if a bit labored in its eccentricity.
If any random character up and flew away during “An Invisible Sign,” it wouldn’t be at all surprising: A tone of fanciful absurdity is maintained throughout, beginning with the animated sequence that opens the film, which harks back to the Grimm-est of fairy tales: In an overcrowded kingdom of yore, the king declares that each family must give up a member for execution. One family, which owns the local bakery, suggests that each member give up a piece of himself or herself instead — an ear, fingers, etc. The daughter gives up a leg.
Back in the reality-based world, Young Mona (Bailee Madison) enjoys a close relationship with her father (John Shea), sharing his love of mathematics and running, until the day Dad has a breakdown. Whether it’s a minor stroke or the onset of depression or schizophrenia is unclear, but in any event, Mona starts making math-based deals with God. If she skips rope exactly 43 times, for instance, Dad will get better. He never does. Mona, meanwhile, grows up to look like Alba, so something’s working out.
Thrust out of her home by Mom (Braga) for no evident reason, Mona is a bit adrift. She never finishes college and has a hard time holding down a job until her old school principal (a terrifically daffy Marylouise Burke) hires her as a math teacher, thanks to a lie that Mom has told on Mona’s behalf. The socially inept Mona, who relentlessly taps out numbers on whatever wooden surface is at hand (we see the numbers, in one of the film’s nicer adornments), is a sitting duck for obnoxious kids, and her class is full of them — except Lisa (Sophie Nyweide), whose mother is dying of cancer, and who latches onto Mona like a baby kitten.
Mona’s wacky orbit, which she traverses in mismatching neo-hippie couture, also includes the local hardware store owner, Mr. Jones (Simmons), who used to be her math teacher and in fact helped inspire her OCD math obsession — a dubious distinction, especially since he seems obsessed himself. It’s unclear whether Mr. Jones is actually in on the numbers conspiracy in Mona’s head, which, under a helmet of bangs and two unruly pigtails, is one unsettled place. Numbers add up to a mystical element in the film, falling somewhere between the madness-inducing obsession of “A Beautiful Mind” and the savant-ish device of “Rain Man.”
Intending to straighten it out is Ben Smith (Chris Messina), the science teacher, who has his students lie about the school impersonating symptoms of dread diseases as a teaching exercise. Amid the general oddity of “An Invisible Sign,” it’s the arc of Ben and Mona’s relationship that serves as a throughline, along with Mona’s realizations about Dad, math and the quite likable Mr. Jones.
Agrelo, whose first film was the dance docu “Mad Hot Ballroom,” demonstrates great instincts with children, even the brattiest, and despite the accelerated reality of “An Invisible Sign,” the kids always seem pretty real. Production values are good, notably the whimsical animation.