I just saw "Merely Marvelous: The Dancing Genius of Gwen Verdon". I rented it on Amazon. I really loved it. I especially liked the part that she was the main person who sought to secure the right to the play "Chicago", from the original author. As I understand it, she tried for many years to secure the rights from Maurine Dallas Watkins. When the author passed away, her heirs allowed Gwen Verdon to have the musical rights to the play "Chicago".
"Noel [Coward] and I were in Paris once. Adjoining rooms, of course. One night, I felt mischievous, so I knocked on Noel's door, and he asked, 'Who is it?' I lowered my voice and said 'Hotel detective. Have you got a gentleman in your room?' He answered, 'Just a minute, I'll ask him.'" (Beatrice Lillie)