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Official Site: DC Comics

Secret (Greta Hayes) is a fictional character appearing in American comic books published by DC Comics.

Secret first appeared in a one-shot comic, part of the Girlfrenzy fifth week event, by Todd Dezago and Todd Nauck called Young Justice: The Secret, in which Robin, Impulse, and Superboy helped her to escape from the DEO (Department of Extranormal Operations) agents who were holding her against her will. Secret was incorporeal, able to take on a variety of appearances, and is referred to as "the mist girl" or "the bottle girl" by the various agents who pursue her throughout the run of Young Justice.

Eventually, her origin was revealed: Secret was once an ordinary girl named Greta, whose adoptive brother Billy killed her as part of his plan to become the supervillain Harm. Because of the manner of her death, Greta remained stuck on this plane of existence, a gateway between the living and the dead. Billy himself, after attacking the team, died when his own father shot him. Billy returned during the Day of Judgment storyline, as the entirety of Hell had been evacuated. He again battled the team, using the substance of Secret.

Secret joined Young Justice along with Wonder Girl and Arrowette. She was often referred to as "Suzie" because her real name was unknown at the time. Secret became good friends with the two girls, and was often portrayed as shy. She nursed a crush on Robin throughout the series, and often defended his actions and followed his leadership without doubt. She also expressed jealousy of Spoiler, Robin's girlfriend, to the point where the pair of them had a full-out battle across Gotham City, that was stopped by the combined efforts of Red Tornado and Robin.

Secret has not been a contender in any CBUB matches.