The former Gossip Girl star is one of a number of actresses featured in a three-part documentary called A Path Appears, which aims to shed light on sex trafficking in the United States.
Along with Pulitzer Prize winning journalists Nicholas Kristof and Sheryl WuDunn, Lively visits with victims of sex trafficking in an attempt to shed light on the global issue.
"I thought of sex trafficking as something that happened elsewhere," she says upon hearing that 300,000 girls go missing each year in the US. "To see it happening in the United States, it seems sort of impossible. ... You can't fathom that this is sort of a prevalent issue, because where are these girls coming from?"
In the first episode, which also features Malin Akerman and Ashley Judd, Lively visits the organisation My Life My Choice, which works with survivors of sex trafficking.
"The most powerful thing is for women not just to be the beneficiaries of the change, but to be agents of it," Lively says of the experience. "My Life My Choice is such a powerful organsation because it utilises survivors."
You can watch a clip from the show below: