Question: Generate a question about the following movie plot: This comedy tells the story of Marc Pease, a grown man living life vicariously through recollections of youthful glory. Ten years out of high school, he's a man still living in the past, when he starred in his high school's musicals. Over the course of one day, events come to a head. While watching from the sidelines as his former teacher/mentor Mr. Gribble oversees the opening night of another show, Pease has an epiphany. Through a cathartic, hilarious process, he finally exorcises his demons and realizes there's more to life than the roar of the greasepaint and smell of the crowd that is Broadway. Over the course of the film, a young high school senior girl becomes romantically involved with both of the men. This only serves to complicate matters.
Answer:
Who is the former teacher/mentor?