Guardians of the Galaxy screen superhero Zoe Saldana is doing her part to help others in the real world. The actress appears in Sia's new "Free Me" music video, which aims to support the #endHIV Campaign and the Abzyme Research Foundation.

Julianne Moore narrates "Free Me," explaining at its start that Saldana's character is an expectant mother with HIV "taking hold in her body, attacking her immune system. And, if left untreated, [it] will be passed on to the baby growing inside her.”

As "Free Me" progresses, Saldana goes into a sad but also hopeful interpretive dance with other performers. At the end of Sia's new music video, Saldana is happily holding her new baby, who is seemingly healthy and HIV free. Moore then says, "Go to to support a promising new AIDS cure."

According to Entertainment Weekly, "Free Me" purchase proceeds go to the #endHIV Campaign, "where the money will 'be used to advance a new potential HIV/AIDS cure to human clinical trials.'" "Free Me" (below) is now available.

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