Djimon Hounsou and Jennifer Connelly will appear in the PSA to raise awareness about hunger in areas of Africa where some human rights activists say the diamond trade helps finance brutal dictatorships.
The title of the new Warner Bros. release refers to gems that are usually mined in war zones and then sold to finance the area's conflicts.
A World Food Program news release said Thursday the two actors will ask the questions:
"What is so powerful that it can make you overcome your greatest fear ... turn your brother into an enemy ... and leave wounds that scar long after the fighting is over?
"What is so potent, it passes effortlessly from mother to child ... from generation to generation?
The answer: "Hunger -- so deadly it kills 25,000 people a day."
WFP officials said they hope the exposure generated by the film will help raise awareness of hunger and poverty, which affect more then 850 million people globally. The film includes footage of aid operations undertaken by the World Food Program in the 1990s.