I think this is the first movie where Zac Efron plays a mature man. His previous films, "High School Musical" (2006) and "17 Again" saw him as Teeny boopies.
Orson Welles apparently is an accomplished actor, painter, magician and director. Remember Citizen Kane. He was borned in US but migrated to UK as a teenager when both his parent passed away.
His early works of art was painting, before he forced himself into a theatre. Acting was what brought him back to the States. Here he built his forte on the Shakespeares. Me and Orson Welles incidently take the Shakespeare's Caeser as the plot.