Muniz gains the trust of the workers at the dump, and takes photos of them which he then enlarges many times. Muniz then involves the workers in artfully arranging garbage - oops make that recycled materials - over the photographs to create a work of art. Muniz then photographs the result.
To see the transformation, here's the original photograph of one of the women and the resulting piece of art that she herself helped to create.
At the left you can see the original picture of Tiao being taken at the garbage dump posed as Marat in the bath tub from a famous painting by Jean Louis David. The next picture shows Tiao looking at the art from a catwalk with the garbage spread on it. That picture gives you a sense of the scale of the art work before the final photograph is taken.
The movie shows Tiao's triumphant trip to London with Muniz where his photograph is auctioned for $56,000. In all, the art work sold for $250,000, all the proceeds of which was donated to the Catador Association. The dump is to be closed in 2013, so the money will be put to education and retraining.
This was a very uplifting movie.