Matt Damon has joined up with Cindy McCain, Michelle Obama, New York City mayor Mike Bloomberg, and many others to once more get behind the ONE campaign and help fight poverty and disease. Damon has traveled to Africa twice for the organization — which includes 100 of America’s most well-known and respected non-profit, advocacy and humanitarian organizations.

In the video, Matt looks directly at the camera while his voice changes to reflect the various other celebrities involved. “The ONE Campaign isn’t about taking sides, it’s about taking action,” Damon said. “America is saving millions of lives in the poorest parts of the world — I saw it myself in Zambia and Tanzania.”

The ads will air on television starting August 24th. Can you guess who’s speaking when? What do you think of the effect?