An article posted on The Hollywood Reporter offers some insight on the process (and the timing associated with each potential selection) director J.J. Abrams went thru in assembling the cast for Episode VII.
It took nine months of meet-and-greets, script readings and screen tests, all conducted with more secrecy than a raid on the Death Star, for director J.J. Abrams, Lucasfilm and Disney to assemble the cast of Star Wars: Episode VII: John Boyega, 22; Adam Driver, 30; Domhnall Gleeson, 30; Oscar Isaac, 35; Daisy Ridley, 21; Andy Serkis, 50; and Max von Sydow, 85, who were unveiled April 29, will join original stars Mark Hamill, 62, Carrie Fisher, 57, and Harrison Ford, 71. Abrams cast a wide net, with actors asked to read material that was not from the top secret script. They couldn’t tell anyone for which parts they were reading, and their agents and publicists had to sign strict nondisclosure agreements.
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