There's no doubt in anyone's mind that Joan Rivers is a piece of work, but what makes someone want to film a documentary about the long-time comedian, actress, red carpet host and all-around entertainer? With two previous Sundance documentaries under their belt (The Devil Came on Horseback, The Trials of Darryl Hunt), directors Ricki Stern and Anne Sundberg return to the festival for a third time with Joan Rivers - A Piece of Work, a documentary that sets out to explore Rivers' wild career on and off the screen.

Cinematical caught up with Stern and Sundberg in an effort to learn a little more about the doc before it premieres in the U.S. Documentary Competition section at Sundance.

Cinematical: Give us the "word on the street" description of your film

Ricki Stern/Anne Sundberg: Joan Rivers a piece of work – takes the audience on a year long ride with Joan Rivers in her 76th year of life, it peels away the mask of an iconic comedian exposing bare the struggles, sacrifices and joy of living life as a ground breaking female performer.

It's an emotionally surprising and revealing portrait, and many people will come away saying, wow, I have a new understanding and appreciation for Joan and her career.