Todd Mc Carthy of Variety criticized her break from the big screen but felt that, despite a performance of "tender feeling", "her natural vivaciousness and spontaneity are straightjacketed" by the film noir format.
Afterwards, Mc Adams starred with Tim Robbins and Michael Peña in the road trip comedy-drama The Lucky Ones, a story about three Iraq War soldiers on a brief road trip back in the United States.
In 2005, she starred in the romantic comedy Wedding Crashers, the psychological thriller Red Eye, and the comedy-drama The Family Stone.
She was hailed by the media as Hollywood's new "it girl", and received a BAFTA nomination for Best Rising Star.
while Roger Ebert of the Chicago Sun-Times asserted that "she brings more presence and credibility to her role than is really expected; she acts without betraying the slightest awareness that she's inside a genre.
Her performance qualifies her for heavy-duty roles." In late 2005, Mc Adams starred with Sarah Jessica Parker and Diane Keaton in the seasonal family comedy-drama The Family Stone, which gave Mc Adams an opportunity to play a dishevelled and sardonic sister, rather than the usual "obvious" girlfriend or wife roles.
After a two-year break, Mc Adams starred in two limited release films in 2008; the film noir Married Life and the road trip drama The Lucky Ones.
She returned to prominence in 2009 by appearing in the political-thriller State of Play, the science-fiction romantic drama The Time Traveler's Wife and the mystery action-adventure film Sherlock Holmes.
Mc Adams' break-out role came in 2004, when she starred in the comedy film Mean Girls opposite Lindsay Lohan, Lacey Chabert and Amanda Seyfried, based on Rosalind Wiseman's book Queen Bees and Wannabes.
Mc Adams was 25 years old when she was cast as the mean high school queen bee Regina George, and she modelled her character on Alec Baldwin's performance in the drama Glengarry Glen Ross (1992).
Mc Adams played Della Frye, an online reporter who investigates a possible conspiracy with Crowe's character, a veteran print journalist.