OK, I'll admit that I reviewed this movie with a distinct bias. "Riding in Cars with Boys" is based on Beverly Donofrio's memoir, which I have read. In her book, Donofrio details how she became pregnant at 15 and married her baby's father, a high school dropout named Ray. Donofrio, a star student in high school, watched her dreams of going to New York University derail as she faced the reality of being a teenage wife and mother. The novel is both compassionate and warm. Donofrio discusses her strengths and weaknesses with a witty candor that both engages and entertains the reader.

Donofrio co-produced the movie, so I was expecting good things from the adaptation. Unfortunately, the book's charm is totally missing in the movie.

"Riding in Cars with Boys" follows Beverly (Drew Barrymore), now a 35-year-old writer, while she drives with her son, Jason (Adam Garcia), now 20, to meet her ex-husband, Ray Hasek, and get him to sign legal papers allowing her to publish her first book, a memoir, without Hasek being able to sue her.

The bulk of the story is told through flashbacks, but director Penny Marshall ("A League of their Own") does not create smooth segues between the current action and the contrasting memories of Garcia and Barrymore. Marshall pays great attention to the detail of the period, recreating the dresses, hairstyles and music of the 1950s through 1980s perfectly; however, the script does not engage the audience as much as the set does.

Screenwriter Morgan Ward seems unable to translate the power of Donofrio's prose to the big screen. She often underwrites the supporting cast, making them seem two-dimensional and more like props than actual people. The result is an uneven film that magnifies the holes in both the script and the actors' performances.

Ray Hasek, played by Steve Zahn, loses the endearing quality he retains throughout the novel. Hasek, instead of being a hapless man who tries his best to be a good husband and fails miserably-thereby illustrating the limitations of good intentions, just seems like a loser from the beginning of the movie, and one wonders why Donofrio would marry him in the first place.

Beverly, portrayed by Drew Barrymore, fares no better. Barrymore seems unable to find a focus for her tremendous energy and spends a good deal of the movie seeming to play Drew Barrymore. Even when the script calls for more serious action-such as when Hasek (Zahn) tries to quit heroin and is going through withdrawals in the room adjacent to the one where their son is trying to sleep-Barrymore does not give these plot developments their due. Barrymore bounces around like a cheerleader, as she and the script seem to make a joke out of the seriousness of addiction and its debilitating effect on her young son, Jason, played adorably by Cody Arens. That said, I hope Barrymore will continue to stretch herself with serious roles. Future scripts hopefully will be better developed so as to give her a true challenge.

"Riding in Cars with Boys" has the makings of a good movie. However, Donofrio and Marshall rush through comic gems only to linger on inconsequential moments such as snow falling as Barrymore drives. James Woods and Lorraine Bracco, who deliver good performances as Barrymore's beleaguered parents, are given too few moments to shine, as is Brittany Murphy, who plays Barrymore's best friend. One leaves the movie unsatisfied, not only because of what was on the screen but also because of what could have been.