The masked gunman arrested for the shooting rampage, who later told police he was The Joker, is a highly educated PhD neuroscience student.
James Eagan Holmes, 24, is alleged to have walked into theatre number nine of the Century 16 cinema in Aurora, Colorado, during a midnight screening of The Dark Knight Rises and opened fire on the audience, using four different weapons to murder a dozen people.
Dressed head to toe in black combat clothes and sporting dyed red hair and a red goatee, he then calmly left the cinema and told police that he was The Joker, a senior police officer revealed.
Last night, as Holmes was still in police custody, a picture was starting to emerge of him as a well-educated young man who had never previously been in trouble with the police, save for a single traffic infringement.
Raised in California by his parents Arlene and Robert, he moved from San Diego to Colorado after graduating from The University of California, Riverside, in 2010 with a degree in neuroscience.