Mona Lisa Smile stars Julia Roberts as Katherine Watson, an unconventional teacher at Wellesley College (a historic all-women's college in Massachusetts) in the 1950's who inspires her students to look beyond the traditional roles assigned to women during that time; it also features a talented supporting cast that includes Julia Stiles, Kirsten Dunst, Maggie Gyllenhaal, Marcia Gay Harden, Topher Grace, and Dominic West.

Unfortunately, all the talented actors in the world can't save a film from a mediocre script.

The premise--new teacher arrives at conservative educational institution to find the students and faculty hostile to her practice of teaching outside the prescribed curriculum, but over time manages to win some of the over and change their lives in the process--has been done successfully before, most notably in Dead Poet's Society.

Like Dead Poet's Society, Mona Lisa Smile does an excellent job of creating the setup, of conveying a world where rules and restrictions abound and female students are so well trained, they don't even question the rules. The shallowness of the Wellesley girls' lives reflect the shallowness of their expectations, which is simply to get married--as if that were a full-time occupation, as if life ended there.

The film also overflows with interesting characters--or rather, characters who would be interesting if you got to know them better--and the acting in the film is consistently excellent. There are moments in which you glimpse what the film could have been, like Ginnifer Goodwin's portrayal of a girl accustomed to rejection who starts to hope for the first time, and the heartbreaking scene in which Gyllenhaal's character Giselle reaches out to console a terrified and angry Betty.

But ultimately, these scenes can't make up for the lack of a coherent, compelling narrative, which is where Mona Lisa Smile parts company with a film like Dead Poet's Society.

The problem with Mona Lisa Smile isn't the message itself--which boils down to "women should have options beyond marriage and motherhood"--but how it's delivered. Female empowerment is obviously an important concept, and there have been plenty of films that have successfully and movingly dramatized issues central to this, like "rape is bad" (The Accused, Thelma and Louise), or "women in power are judged by different standards than men" (The Contender) or "women should be able to play sports" (Girlfight, Bend it Like Beckham).

But for relatively simplistic messages to be successfully portrayed in film, they have to be personalized and conveyed through characters and stories that are compelling on their own. Newell attempts to to do this in Mona Lisa Smile, but never really succeeds; although Roberts' character is sympathetic and interesting, you never really get to know what makes her tick, and there are so many other characters and storylines that, except for Dunst' lonely housewife Betty Warren, you never really get to know any of the other characters very well, either.

One of the vaguely-defined characters in the film is lesbian nurse Amanda Armstrong, played by Juliet Stevenson (who most recently played the mother of Keira Knightley's character in Bend it Like Beckham). A longtime employee at Wellesley still grieving the death of her partner, Amanda gets dismissed by the college early on in the film for providing contraception to students (which was against Massachusetts state law at the time).

Amanda is a relatively minor character whose sole purpose seems to be to make it clear to the audience that the challenges Katherine Watson faces from the school's administration aren't personal, that the school comes down hard on everyone who challenges convention--or to be precise, who gives the appearance of challenging convention.

Still, it is nice to see a sympathetic lesbian character in a big-budget Hollywood picture who isn't depressed, suicidal, or a serial killer, even if she doesn't exactly have a happy ending. Stevenson makes the most of her limited role by infusing Amanda with a bitter wit and survivor's determination that makes her one of the few staff members at Wellesley that Katherine Watson comes to like.

Some viewers may wonder whether Amanda's existence in the film is an product of revisionist history, if perhaps she was inserted in the film merely to appeal to modern interests (since lesbians are so trendy these days). But in real life, there have been a handful of openly lesbian professors at Wellesley since the school was founded (including English professor Katherine Lee Bates who in the 1890's wrote the now-famous anthem "America the Beautiful").

In the film, Amanda's sexuality is an open secret known by school staff and administration alike, in part because her companion of 31 years was a biology professor at the college. Amanda's sexuality never jeopardized her career because it was never officially made public, even though everyone knew about it. Similarly, Amanda was dismissed not because she dispensed contraception to students, but because an editorial in the student newspaper made public what she was doing, forcing the school to take action to something they had turned a blind eye to previously.

This is a relatively accurate reflection of the environment at Wellesley and other colleges like it in the 50's, which tended to harbor progressive-thinkers but had to conceal that fact or risk jeopardizing enrollment.

But the movie ultimately disappoints because although it's good enough to watch, with such an experienced director (Mike Newell, whose numerous films include Traffic, Four Weddings and a Funeral, and the upcoming Harry Potter and the Goblet of Fire) and boasting such an excellent cast, it should have been great.

Instead, you come away with a vague sense of a mildly entertaining film with characters who are interesting but not very well defined, and the message that sexism is bad--but not because the message was given life by the film, but simply because it was repeated so often.