Giant tells the true story of children's author Roald Dahl and the scandal that tarnished his legacy. Written by Mark Rosenblatt and directed by Nicholas Hytner, John Lithgow reprises his Olivier-winning role as Dahl on Broadway. Giant opened on March 23 at the Music Box Theatre, and Broadway.com spoke to the cast and creative team on the opening night red carpet. The play, which is set in 1983, first premiere…