Betty Anne (Hilary Swank: Amelia) and Kenny (Sam Rockwell: Iron Man 2) are tight-knit siblings bound by hardship and mischief. Kenny’s a little more mischievous, though, and the favorite suspect of local cops winds up serving a life sentence without parole when they pin him for a vicious murder. Against staggering evidence, Betty Anne devotes her life to winning his freedom, eventually going to college to become a lawyer and working with new friend Abra (Minnie Driver: Take) to exonerate him through DNA evidence after 18 years of wrongful imprisonment.

The movie, adapted from the siblings’ true story, is part legal drama, part portrait of a sister’s devotion. Actor turned director Tony Goldwyn (The Last Kiss; perhaps best remembered as the villain from Ghost) pieces together a tale of ambitiously broad scope as a patchwork of long-term legal struggle and lifelong flashback.

The collage effect yields fine substance. Goldwyn fleshes out empathetic characters and their profound relationship while building empathy for the cause. Flashes of childhood struggle through impetuous young adulthood build a whole view with ample context.

Still, it’s a broad scope, and the movie stumbles in the constant, capricious shuffle of snippets from filmic present and wide-ranging past. Key touchstones move the plot and offer decent drama, but the movie is short on dramatization to build bridges between those moments or delve to the heart of struggle. They instead lapse into a “so this happened” two-step solely through Betty Anne’s perspective, bouncing between points in her struggle without taking a care to knit out a smooth narrative. One moment her husband is frustrated by her obsession, the next she’s a kid stealing candy with her brother, and then she’s on a prison visit discussing his case. Timeline often loses sense of scale as the two-step loses rhythm. Further, the limited perspective helps to neglect worthy portions of the tale: Kenny’s prison term is reduced to measured glimpses, and his estranged daughter is presented as an afterthought.

Weirdly, the richest, most contentious elements of conflict — the shoddy police work of a corrupt officer; the political stubbornness of a resistant district attorney — are barely touched upon. Where’s the energy? In fact, more focus is granted to the effort to compel an elderly clerk to actually look for a box of evidence. Sure, it’s a critical point, but it’s a strange choice for storytelling. Desperation and sister’s personal sacrifice serve the only tension. It’s gripping for a while but eventually drones into thematic monotone.

The film presents an interesting and emotional tale with solid performances and engaging vignettes, but it doesn’t click as a comprehensive drama. Perhaps the filmmakers were being careful not to sensationalize. In the end, though, it seems they sold the story short.

Fair • R • 107 mins.