As Dear Frankie opens, Emily Mortimer has packed up her family for the latest in a series of cross-country moves. They wind up in Glasgow, but as Mortimer's 9-year-old son (Jack McElhone) observes, it looks like the end of the earth. Clearly, exhaustion has begun to set in, even if McElhone doesn't yet have Mortimer's tired eyes to show for it. At least his grandmother (Mary Riggans) seems to have gotten used to the exhaustion. Mostly, she just sits in their new apartment and smokes, much as she must have sat in their old apartment and smoked. For a family on the move, they don't get out much.
There are reasons, of course. McElhone is deaf, and while Mortimer is determined to give him a normal life, she's just as determined to protect him from harm. Given that her own normal life resulted in a marriage to an abusive man whose attempts to contact her keep her on the run, there's a logic to this, just as there's a logic to her decision to comfort McElhone with a fictionalized, reinvented dad, a nice sailor chap who keeps in touch via regular letters that Mortimer composes in secret. The fiction can only hold for so long, however, and when one of McElhone's classmates points out that his "dad's" ship will be in port soon, Mortimer is forced to take desperate steps to keep up the façade.
Dear Frankie serves as an example of how fine acting, subtle direction, and a strong sense of atmosphere can steer potentially mawkish material away from excess. Explosive one moment, tender the next, Mortimer captures a woman going about the tough business of motherhood. After all, no one else is going to do it. Expressive without speaking, McElhone suggests a kid who's already learned more lessons from his mother than she could imagine. The hazy, seaside setting, evocatively photographed by debuting director Shona Auerbach, drains the story of sentimentality as effectively as Auerbach's tendency to favor awkward pauses and knowing looks over spell-it-out dialogue. An even better film might have dug into the ethics of Mortimer's choice to favor a comforting lie, or avoided a few too-convenient late-film developments that let almost everyone off the hook, sending them toward a happy ending. But on its own terms, Dear Frankie works much better than it really has any right to. Auerbach tells a small, contrived story, but gives it the weight of life.