Joe Mangianello, who debuted as Deathstroke in a Justice League post-credits scene, is now set to reprise the role in a solo film. But at one point he was supposed to suit up as the DC mercenary in Ben Affleck's The Batman, and he was so committed to the part that he actually wrote more than a dozen pages of the character's backstory.

Speaking with Chris Hardwick on the ID10T podcast, Mangianello said he played a substantial hand in the planned Deathstroke movie. Six months before talks began with director Gareth Evans, Mangianello wrote 16 pages of backstory that became a treatment and eventually led to a Skype call with the filmmaker.

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He said he finds Deathstroke and the circumstances of his life, such as his twisted family and the loss of his eye, to be utterly fascinating. "This is a real opportunity to figure out who this guy is on the inside," he said. "There are villains who are the people who are opposing them but from the inside this is a person who is struggling with all types of things."

Deathstroke has been a significant player on The CW's Arrow, where he was portrayed by Manu Bennett, but the character didn't become involved in the DC Extended Universe until Justice League.

News about the solo movie has been scarce, but Mangianello assured earlier this month that "there are things in the works."

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(via LRMOnline)