It's the 1980s and siblings Betty Anne Waters (HILARY SWANK) and Kenny Waters (SAM ROCKWELL) have always had a special bond due in part to having grown up in various foster homes thanks to a decidedly less than good mom. Now young adults, Betty Anne has matured more than her brother who's no stranger to run-ins with the law. That reputation eventually comes around to haunt him as Ayer, Massachusetts police officer Nancy Taylor (MELISSA LEO) arrests him on suspicion for the brutal murder of a local woman in 1980.
Although he's released, two years later he's arrested again for that crime and then convicted to serve the rest of his life in prison, thanks to testimony by the mother of his young child along with his lover, Roseanna Perry (JULIETTE LEWIS). Kenny claims he's innocent, but no one believes him. That is, except for Betty Anne who decides the only way for her to get him out is to attend and then graduate from college and then law school, and then pass the bar in order to become his lawyer.
That commitment eventually causes her husband, Rick (LOREN DEAN), to leave her, while their kids, Richard (CONOR DONOVAN) and Ben (OWEN CAMPBELL) eventually have enough moments of disappointment with their mom that they decide to move in with their dad. Yet, Betty Anne continues on her quest, helped by fellow law school student Abra Rice (MINNIE DRIVER) and eventually Innocence Project founder Barry Scheck (PETER GALLAGHER) who states they might be able to do something if DNA samples can be recovered.
As Betty Anne tries to do just that -- despite the many years that have passed since the initial trial -- and hopes to convince her now young adult niece, Mandy (ARI GRAYNOR), that her father is not the murderer she's been led to believe, she must overcome various setbacks that threaten to derail her effort to prove her brother's innocence.