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In the narrative behind why Jesse killed Riley in Terminator: The Sarah Connor Chronicles: Today is the Day - Part 1 (2009), it is revealed that she had planned right from the start and frame Cameron for Riley's murder, so she could destroy John's trust in Cameron. Jesse had a deep hatred for Cameron and had lost all respect for John because he recruited machines. It was her personal mission to destroy the trust and relationship between John and Cameron and she brought Riley Dawson with her from the future and used her as the tool to achieve her goal.
In 2012, online petitions were set up for the series to be brought back and a 3rd season to be commissioned. The campaign to bring back the series continued even throughout 2015.
Summer Glau got the role of Cameron based partly on the strength of her fight scenes in Serenity (2005). Josh Friedman wrote the character with Glau in mind.
The character "Cameron" is a tribute to James Cameron, who wrote and directed The Terminator (1984) and Terminator 2: Judgment Day (1991).
This series effectively 'retcons' Terminator 3: Rise of the Machines (2003), continuing the Terminator universe from the end of Terminator 2: Judgment Day (1991).
Summer Glau initially did not want to audition for the role of Cameron Phillips, believing she did not look right for the role. However, her mother Mari convinced her to go to the audition and Glau ended up getting the role.