Octavia Spencer, who stars in the latest box office hit Hidden Figures, has bought Saturday's showing of the historical drama at Rave Cinemas Baldwin Hills in Los Angeles to honour her mum and "all the single parents".
"If you know a family in need that would like to see our movie but can't afford it have them come," she wrote on Instagram. It's first come first served.
"My mom would not have been able to afford to take me and my siblings. So, I'm honoring her and all single parents this #mlkweekend [Martin Luther King weekend]. Pass the word."
The US honours Martin Luther King on January 15, the date he was born in 1929.
Fox's Hidden Figures recounts the little-known story of three African-American women whose work at NASA helped the US in its competition against Russia in the Cold War's 'Space Race', or capability in space technology.
Ms Spencer's call-out to has been met with praise on social media.
Daveydayla wrote on Instagram: "I'm near tears. As a child raised by a single parent I applaud you Octavia.
"Your thoughtfulness is not unnoticed. God bless."
While Papillionart commented: "This is truly exceptional. I've been a huge fan of yours for so many years and I understand why."
MORE NEWS ABOUT FILMS
Arrests for not standing for Indian anthem at film festival
Mary Jackson (Janelle Monae, left), Katherine Johnson (Taraji P. Henson) and Dorothy Vaughan (Octavia Spencer) in a scene from 'Hidden Figures'. Source: AAP