She is portrayed by Lesley-Ann Brandt.
Larissa Diaz is first seen observing Wayne Manor. When questioned by a gardener, she chokes him and has him killed by her associates, and then smears blood over her face. She knocks on the door in which the butler and Bruce Wayne's guardian Alfred Pennyworth answers and she pretends to be the victim of an accident. When Bruce Wayne and her target Selina Kyle asks what is going on, both Diaz and Selina lock eyes. Alfred works out something is wrong, tells the children to run and fights Diaz and her associates. Diaz manages to get away and Alfred takes out a couple of her associates and Bruce and Selina manage to escape to Gotham City.
She was later seen looking for Dick Lovecraft, who was in the process of telling Detective James Gordon something vital about the murder of Thomas and Martha Wayne until she turned up at his apartment. She told Gordon if he stood down she would not hurt him. Gordon feigned surrender and was knocked out by her associate.
She took his gun and shot Lovecraft dead with it, taking the vital files relating to the Wayne murders with her. She got contacted by a fence known as Clyde who managed to capture Selina and Bruce. As they tried to escape Alfred and Gordon showed up and got into a firefight with her henchmen.
She questioned Bruce where Selina was but he refused, saying she had escaped. Spotting Alfred, Diaz fled, but not before telling Bruce not to confuse bravery with good sense.
What became of her after is unknown, but doesn't seem to be going after Selina Kylie anymore (who retracted her statement of seeing the man who killed Thomas and Martha).
- There have been different versions of Copperhead in the DC Comics, but they are male. A female version first appeared in the 2013 video game Batman: Arkham Origins.