A mere month ago, The Martian Child showcased John Cusack as a grieving widower raising a troubled child on his own, and trying to decide how to provide comfort without inflicting further damage. In the broadest of particulars, Cusack recapitulates that role in the Sundance Audience Award-winner Grace Is Gone, but the films' tones could hardly be further apart. Where Martian Child started off sweetly sentimental and turned cloying, Grace Is Gone starts raw, gets rawer, and fights for honesty over commercial calculation.

Early on, Cusack learns that his soldier wife has been killed in action in Iraq. Dealing with her death and breaking the news to his children (newcomers Shélan O'Keefe and Gracie Bednarczyk) would be difficult under ordinary circumstances, but Cusack's political conservatism and personal convictions make things even more awkward. He supports the military so devoutly that he cheated his way into the Army, where he met his wife before he was booted for the poor eyesight he tried to conceal. He firmly believes in the Bush administration and the Iraq War. So how to explain to his children that it robbed them of their mother? Panicking and in denial, Cusack puts off the moment, first distracting the kids at Dave & Busters, then setting off on an episodic cross-country trip to a theme park, in what becomes a morbidly bleak, indie-miserablist twist on National Lampoon's Vacation.

Cusack's alternately weepy, manic, and robotic affect in Grace Is Gone doesn't always work; his character's choices call for strained logic and overtaxed emotions, and he seems strained and overtaxed in response, in spite of the film's generally elegiac, low-key tone. Grace Is Gone works mostly because of O'Keefe and Bednarczyk's amazing performances. Bednarczyk is adorable and convincing as a young child caught up in the excitement of an unexpected break in routine, but O'Keefe is heartbreaking. Perched on the cusp of puberty, she's just old enough to suspect that something's horribly wrong, but also still enough of a child to be momentarily seduced by Cusack's giddy, desperate distractions, and the subtle complexities of her portrayal recall a young Sarah Polley.

Grace Is Gone attempts to address grief frankly, gently, and without didacticism, and it largely succeeds. Though he tries a little too hard to push emotional buttons, debuting writer-director James C. Strouse has the sense to touch on the moral questions of Iraq only briefly and lightly, and without preaching or coming to any pat conclusions. Instead, he concentrates on the characters, and he finds all the answers he needs right there on O'Keefe's sensitive, uncertain face.