Joan Rivers takes pleasure in being called "the Queen of Comedy." In this intriguing and very entertaining documentary by Ricki Stern and Anne Sundberg, we see a year in the life of this 75-year-old legend who has been at it for 44 years. Devotees of comedy will appreciate the clips of Rivers performing on Jack Paar, Mike Douglas, Johnny Carson, and other tv shows. Writing jokes and telling them isn't a piece of cake. Rivers shows us her expansive card catalog collection of 30 years of jokes.

In one of the most revealing segments on the documentary, we see her preparing to launch her biographical play Joan Rivers: A Work in Progress by a Life in Progress. It is received warmly in Edinburgh but then falls off a bit when performed in London. Fearing a verbal personal attack by New York critics on Broadway, Rivers decides to dump the play. There is real pain and sadness in her face when she laments: "No one will ever take me seriously as an actress." It turns out that is the only thing she really ever wanted and now it is out of reach once again.

This probing documentary proves that Rivers is a complicated person who loves her "creaturely comforts." She has a huge apartment and a large staff but she worries constantly about money. She is ecstatic about landing a spot on Celebrity Apprentice since the reality show will give her more "Face Time" and lead to new work. Rivers demonstrates fortitude by attending the Kennedy Center tribute to George Carlin, she endures a Comedy Central roast and she travels to Wisconsin to appear in the showroom of a casino.

In these and other sequences, Rivers comes across as a real trooper who has overcome plenty of setbacks and disappointments. She talks about a long and painful rift with Johnny Carson, her mentor and avid supporter; the failure of Fox television show, the suicide of her husband, and troubles with her daughter. A warm and kinder side of the comedian comes across in segments on her charity work. After delivering a meal to a woman, she Googles her and laments how this once-talented photographer now suffers from illness. Real compassion is evident in this brief scene.

Perseverance is a worthwhile virtue and it serves as an antidote to the criticism of Joan Rivers as a workaholic who is addicted to fame. She really does love what she is doing and when she's on stage, it is clear that her immersion is 100%. That is not an addiction but a total delight in making people laugh. And that rare quality demands our respect!

Special features on the DVD include deleted scenes; a commentary; TV spots; and a Sundance Q & A.