WHEN YOU’RE AN international superstar-when you’re Julia Roberts or Tom Cruise, for example-it can be difficult for audiences to accept you in challenging roles, difficult for them to dissociate the persona from the performance. Lately this phenomenon also has been true of Angelina Jolie, with her well-documented adventures in adoption and globe-trotting with Brad Pitt.

But in “A Mighty Heart” as Mariane Pearl, the wife of slain Wall Street Journal reporter Daniel Pearl, Jolie reminds us that she really can act, that the supporting-actress Oscar for “Girl, Interrupted” wasn’t a fluke, that there is indeed substance beneath the sex appeal. She deeply immerses herself and, as a result, stands tall as the film’s graceful heart and soul. It’s pretty hard to imagine that her name won’t be at the forefront again come awards season this year.