Cross cultural friendhip can make such a difference. The long-awaited documentary telling the story of a local friendship that helped save Annapolis from riot 40 years ago will be previewed Saturday at Maryland Hall for the Creative Arts. "Pip and Zastrow: An American Friendship," has been in the works for more than two years and is finally ready for the screen. Award-winning documentary film makers Victoria Bruce and Karin Hayes took to the subject after hearing the unlikely story: A friendship between a white kid and a black kid struck up on the basketball court which grew to save their town from the rioting that broke out nationwide following the assassination of the Rev. Martin Luther King.