Asa Maxwell Thornton Farr Butterfield is an English actor who formerly portrayed the character of Mordred in the Series 1 episode The Beginning of the End and later returned to reprise the character in The Nightmare Begins and in The Witch's Quickening. The role was later recast with older actor Alexander Vlahos who portrays Mordred in Series 5. Asa was 11 years old when filming The Beginning of the End in 2008.
He played the Brethren Boy in Son of a Rambow which was released in 2007.
Asa has also played the lead, Bruno, in the film The Boy in the Striped Pyjamas.
He also played Norman Green in Nanny McPhee and the Big Bang.
He played the title role, Hugo, in the critically acclaimed movie, Hugo that was released in 2011.
Asa is also starring as the main character in the 2013 movie, Ender's Game.
Asa's nickname is "Bopp" as he was born on April the 1st 1997, a comet named "Hale-Bopp" was seen in the sky for the whole day and night, before disappearing from sight on the morning of April 2nd.
Asa has twitter. His username is : @asabfb (asa bopp farr butterfield).