The Absolutely Fabulous star agreed to spend time with the rapper as part of a new show she is making for the Bbc in which she documents will.i.am's childhood and rise to fame.
During the film, Lumley accompanies the star on a trip back to his childhood home in the Boyle Heights neighbourhood of Los Angeles, as well as the school he attended.
The rapper/producer is also filmed writing and recording a special song about his mother.
Lumley says of the project, "I have long been fascinated by will.i.am and leapt at the chance of meeting him and finding out more about his extraordinary life and achievements. He was everything I had hoped he would be, and more: charming, articulate, a whirlwind of ambition and talent, as sweet as pie and as dandy as a peacock."
Joanna Lumley Meets will.i.am is expected to air in the U.K. in 2014.