THR's Women in Entertainment 2011: Power 100

Just before Thanksgiving, Kroll found herself in London on business, so she decided to stay abroad through the holiday and see friends. "My time is not my own," she confides. That's an understatement, considering she runs global marketing for the most prolific studio in Hollywood -- and one of the most successful.

So far, Warner Bros. has bragging rights to the top movie of 2011, Harry Potter and the Deathly Hallows: Part 2, which grossed $1.32 billion worldwide, the best of any film in the blockbuster franchise. "The opportunity to work on that film was amazing, but I also think there's been a lot of interesting things that weren't so obvious," says Kroll.

PHOTOS: THR's 2011 Women in Entertainment Power 100

In particular, she notes the strong branding campaign for R-rated comedy Horrible Bosses, which paired each of the three employees with their respective bosses, as well as coming up with a color palette for each. "To me, it's more than movie marketing. It's really about getting in there and bringing the concept to life in a way that people can relate to and remember," she says.

She's also especially proud of the campaigns for Crazy Stupid Love and Steven Soderbergh's Contagion, which became a surprise box office hit. "Contagion was amazing, and it was about tapping into people's worst fears," says Kroll, adding that the decision to feature Gwyneth Paltrow's terrified and ailing character on a one-sheet was "unusual and audacious."

Kroll's power base is substantial, and she sits on the studio's greenlight committee. If she doesn't think a movie will work from a marketing perspective, she can vote no. The married Kroll has a truly global view, having been president of international marketing before becoming worldwide marketing president in 2008. She says: "Watching a project evolve and working on the marketing is the best job in the industry."