I knew absolutely nothing about Alfie when this process began, except that he had done some kickass readings for us. His audtion for Theon was particularly strong, especially the scene where Theon returns to Pyke to confront his father Balon (no, that won't be in the pilot, but it was a great scene to use in the sides).
After he was cast, of course, I went to learn more about him on the internet, and discovered all sorts of interesting things. Like the fact that he replaced Daniel Radcliffe as the lead in the West End production of EQUUS, which became one clue -- he has something in common with Harry Potter. Also, he's the young brother of the British pop star Lily Allen. One of her first hits starred Alfie -- being played by a puppet:
(Sorry, embedding is disabled on that one, but check it out. I confess, I am not exactly an authority on today's music, and I had never heard of Lily Allen before Alfie was cast. But in the past couple of weeks I have become a huge fan of her music, especially "Alfie" and "Not Fair." Be warned, though, her songs have plenty of explicit lyrics).