Simplicity — four-square, not sappy — is rare in film. James C. Strouse had it in his script for Lonesome Jim. As writer and first-time director, he gives Grace Is Gonethe quiet power to sneak up and floor you. A reserved father (John Cusack in a devastating change of pace) drives his young daughters, the wondrous Shelan O'Keefe and Gracie Bednarczyk, to a Florida theme park, unable to find words to tell them that their soldier mom has been killed in Iraq. That's it. No politics, no pleading. No artifice.