The epic 13 part Batman story The Long Halloween is finally becoming an animated filmThis two-part adaptation will tell the story of Batman hunting down a killer that only strikes on Holidays. And if that wasn't enough, he must contend with some of his most deranged villains and the increasingly mentally unstable District Attorney Harvey Dent.

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The graphic novel was masterfully written by Jeph Loeb and contains beautiful art by Tim Sale. Christopher Nolan's The Dark Knight also took many of its best elements from the graphic novel. The animated version stars Jensen Ackles as Batman, Naya Rivera as Catwoman, and Josh Duhamel as Harvey Dent. Here are a few details from the upcoming film's trailer that Batman superfans might have spotted.

5 Solomon Grundy Returns Again

Batman Long Halloween Solomon Grundy Attacks

The immortal being known as Solomon Grundy first appeared in All-American Comics #61 in October of 1944. Originally a man named Cyrus Gold, he was murdered and left to mutate in a swamp for over 50 years. He eventually rose again and faced many DC Heroes in battle.

Each time Grundy dies, he comes back to life with a different personality and varying mental capacities. He can return as a mindless brute, or an intelligent mastermind. One thing that never changes, though, is his physical strength. He has gone toe to toe with Superman on more than one occasion. Normally other super villains use him as muscle, but every once and awhile he comes back with devious plans of his own. During his battles with Batman, he has frequently been tough to deal with due to his massive strength.

4 Gilda Dent Will Go Through Some Tough Times

Batman Long Halloween Gilda Dent Staring

The long-suffering wife of Harvey Dent, Gilda has made numerous appearances in Batman comics. For years, she was the only thing keeping the darker sider of Harvey's mind at bay. Eventually he descended into madness and became Two-Face, but Gilda still sought to help the man she once loved.

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In The Long Halloween, Gilda tries to keep Harvey sane while he attempts to take down the Mob in Gotham City once and for all. She witnesses just how Gotham City can pollute and ruin even the best of people. Time will only tell what role she will play in the film. If it's anything like the graphic novel, her character will go through some very dark times.

3 Carmine "The Roman" Falcone Will Make An Appearance

Batman Long Halloween Carmine Falcone At Meeting

Carmine Falcone is one of the most infamous Mob bosses in Gotham City history. He organized crime in the city to such lengths that the city's underworld works like the Roman Empire, earning him the nickname "The Roman". He is also an enemy of both Batman and Catwoman, with the latter having a personal vendetta against him.

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After a childhood injury Carmine suffered, Thomas Wayne, Bruce Wayne's surgeon father, saved his life. This means that every life that Carmine has ruined or taken has weighed on Batman for quite some time. In manner of just desserts, Carmine has had numerous troubles contending with the new breed of criminal that appeared in Gotham following Batman's arrival.

2 The Calendar Man Has A Role To Play

Batman Long Halloween Calendar Man Thinking

First appearing in Detective Comics #259 in 1958, this eccentric villain is not a well-known member of Batman's Rogue's Gallery. It was not until The Long Halloween that Calendar Man was seen as anything more than a cheesy Silver Age villain. Now, he is a demented and genius criminal that enjoys toying with Batman and the Gotham City Police Department.

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Due to his obsessive compulsive nature, he can understand the demented minds of Gotham City's most vile in ways that even Batman cannot. While he does not get in on much of the action in The Long Halloween, he plays a vital role. He derives a perverse pleasure from giving Batman and the GCPD tiny bits of clues to assist in the capture of a killer that only murders their victims on Holidays.

1 The Holiday Killer

Batman Long Halloween Holiday Points Gun

The central mystery at the heart of The Long Halloween is the identity of the Holiday killer. Known as Holiday, this murderer takes on the Mob and various deranged criminals like the Joker without fear. Batman himself has no idea who this killer could be. Eluded at every turn, Batman is pushed to the brink to stop all the chaos caused by Holiday and his disruption of the criminal underworld.

All of this occurs pretty early in Batman's career, and as such, he does not have all the skills required to take down a villain like Holiday. It takes the combined efforts and minds of Harvey Dent, Batman, Commissioner Gordan, and the Calendar Man to even grasp a glimpse of the larger picture. Once Holiday's motives come into focus, viewers will be forced ask themselves just who is right and who is wrong in the morally complex world of the Dark Knight.

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