From the previous episode: The Cast of the "remake" of The Last Starfighter.
As Alex Rogan: Zachary Levi. Winner: Mark
As Grig: Chiwetel Ejiofor. Winner: Arkle
As Maggie Gordon: Carey Mulligan. Winner: Arkle
As Xur: Ray Park. Winner: Mark
As Centauri: Bruce Campbell. Winner: Mark
As Ambassador Enduran: Ian McKellan. Winner: Arkle
As Lord Krill: Tie goes to the Guest. Laurence Fishburne. Winner: Mark
Final Score: Arkle, 3. Mark, 4.
Since Mark won, the "movie" will be directed by his choice of director, Jon Favreau.
Photoshoppers, get to work making a poster. ;-)