James Mottern's directorial debut belongs to the ever-growing subgenre of films where a free spirit is suddenly saddled with a child (see Big Daddy, Raising Helen, Old Dogs, etc.) Though Trucker travels a well-worn road, it sets itself apart with the strong performances from its cast. Lead actress Michelle Monaghan, who has previously impressed in Gone Baby Gone and Kiss Kiss Bang Bang, is particularly notable, giving a raw, unselfconscious turn as the eponymous woman. Trucker doesn't try to make its protagonist, Diane Ford (Monaghan), look good. Instead, the film quickly establishes her hard edges with a cold post-coitus interaction in a hotel room on the road. When Diane returns home, she quickly learns that the child she abandoned as a baby, 11-year-old Peter (Jimmy Bennett), will be staying with her while his cancer-ridden father, Len (Benjamin Bratt), lies in a hospital bed. The interaction between the fierce -- and fiercely independent -- Diane and her equally headstrong son gets off to a shaky start, but inevitably both begin to soften. Diane's close friend Runner (Nathan Fillion) acts as the catalyst in their relationship, even spending time with Peter while Diane leaves town for work. Trucker traffics in cliché -- it's easy to guess the ending from the film's trailer, much less its first few minutes -- but Monaghan's performance is truly remarkable. It's impossible to take your eyes off her, whether she's screaming at her son, threatening teenage bullies, or engaging in easy interaction with Runner. Diane is not the typically likable heroine, and Monaghan gives a startlingly genuine performance, never making the effort to make her character more palatable for the audience. The young Bennett holds his own with the actress, and he doesn't rely on the typical tricks of child actors. Fillion's best previous work (including Firefly, Dr. Horrible's Sing-Along Blog, and Waitress) has capitalized on the actor's charm, and Trucker does the same. However, a number of dramatic scenes prove that Fillion is just as adept as conveying serious emotion as he is with more lighthearted lines. It's unfortunate that such talented actors are saddled with a less-than-inventive script, but their talents make the film watchable.