10 Mind-Blowing Facts You Didn't Know About The DC Animated Universe

From Gotham cop Renee Montoya to teen future Batman Terry McGinnis, Lex Luthor's assistant Mercy Graves, and electricity-powered supervillain Livewire, to name but a few, the original characters created for the DCAU have been a gift to the continuity of DC Comics. None more so than easily the most popular and successful DCAU creation: Harley Quinn.

Since debuting as a one-shot character in Batman: The Animated Series, the Joker's squeaky-voiced female counterpart has become a fixture in not just the DCAU, but also the comics, and now as one of the figureheads of DC's live action movies.

Given that she's been around since 1992, and that she was an almost instant hit with fans, you'd think that Harley would have been the first DCAU character to cross onto the pages of the comics. In actual fact, she didn't make it to the pages of the regular DC Comics universe until Batman: Harley Quinn in 1999, three years after a much more minor character beat her to the punch.

Lyle Bolton, AKA Lock-Up, was created for the eponymous Batman: The Animated Series episode in November 1994. An abusive Arkham Asylum security guard turned extremist vigilante, Lock-Up was an interesting idea, highlighting the narrow boundaries between criminal and crime-fighter which Batman continually has to negotiate, but writer Paul Dini was not hugely happy with how the episode turned out.

Nevertheless, less than two years later the character made his debut in the regular DC continuity, taking Two Face prisoner in Detective Comics #697 in the summer of 1996. It would open the floodgates to countless more DCAU characters making the crossover in years to come.