Batman: In Darkest Knight

Issues
Batman: In Darkest Knight is a one-shot comic book, published in 1994 and written by Mike W. Barr with art by Jerry Bingham. The comic is an Elseworlds story in which Bruce Wayne becomes the Green Lantern instead of Hal Jordan. This one change creates a domino effect which changes many events and characters in the DC Universe. The story draws heavily from related Batman comics, including Batman: Year One and The Killing Joke.

The comic is dedicated to the memory of Bill Finger, who was "present at the birth of both" according to the afterword.

Plot
The story begins after Bruce Wayne's disastrous first attempt at crimefighting. As he sits in his study, wounded, he pleads with his father for some means by which to terrify the criminals of Gotham City. Suddenly, a ghostly image comes from a bust before him, telling him that he has been chosen. The figure heals his wounds and leads him to a crashed rocket on his property. Inside, the dying Green Lantern Abin Sur gives Wayne his power ring and tells him to wait for contact from its masters. Bruce hides the rocket in the cave beneath his mansion and begins his crimefighting career.

His first mission is a botched robbery at a chemical plant, overseen by the criminal Red Hood. Using a combination of his powers and skills, Bruce manages to subdue the criminals and turn them over to Commissioner James Gordon. As Green Lantern flies off, Gordon tells district attorney Harvey Dent that he mistrusts vigilantes, especially those with that much power. Shortly afterwards, the Guardians of the Universe give Bruce his first official mission: stop the errant, power-hungry Sinestro, who abuses his Green Lantern ring for personal gain. Bruce manages to subdue Sinestro, leaving the people he once dominated despondent. When one of them, Katma Tui, says that Bruce is their hero, he gives her Sinestro's power ring before returning to Oa. Sinestro swears vengeance on Bruce before he is banished to Qward.

Back on Earth, Bruce goes to Gordon and asks for help in figuring out the identity of his parents' killer (without divulging his identity). Initially refusing, Gordon later sets to work and has almost found the answer when Sinestro appears, bearing a yellow power ring from the Weaponers of Qward. He steals the information and kills Gordon, then sets off. Sinestro finds Joe Chill and uses his power ring to absorb the man's mind. When Bruce shows up to investigate, he is ambushed by Sinestro, who exhibits dual personalities thanks to Chill's mind. Bruce manages to drive the criminal off, which leads Sinestro to acquire allies on Earth.

Days later, Bruce has an encounter with two criminals, one of whom is a superpowered and mind-altered Harvey Dent. The other is Selina Kyle. Though he defeats them, the pair escapes back to Sinestro, who watches as Bruce sets up a system of observer satellites in orbit. During his absence, Sinestro has been causing chaos on other planets in the sector, causing the Guardians to question Bruce's role as a Lantern. However, he refuses to give up his ring, leading the Guardians to contact three other worthy candidates on Earth to also become Green Lanterns (Clark Kent, Wonder Woman, Barry Allen).

Some time later, Bruce is patrolling the city when four Lanterns, including Katma Tui, attack him and attempt to restrain him. Taking advantage of his distraction, Sinestro leads his forces to attack Bruce's cave, injuring Alfred in the process, and begins tampering with the power battery when the three new Green Lanterns appear and battle the villains. Bruce is subdued, but senses that Alfred is in danger and regains his ring as it responds to his will. Rushing home, he finds that Alfred is dead and that Sinestro has escaped. The three Lanterns beg him to stay and teach them, but Bruce refuses, asking them to protect the Earth while he hunts down Sinestro.

Characters
 Bruce Wayne/Green Lantern: Before Bruce Wayne could witness the bat that would inspire him to take up the mantle of Batman, he was contacted by Abin Sur and became the Green Lantern of Sector 2814 instead. He wears a costume almost identical to Hal Jordan's, but with an earless version of Batman's famous cape and cowl as well as the Green Lantern domino mask.

Sinestro: Green Lantern's traditional enemy, he begins a quest of vengeance against Bruce Wayne following his defeat and humiliation. Along the way, he absorbs Joe Chill's mind, making him act more deranged. Sinestro adopts many of the mannerisms in common with Batman's traditional foe, the Joker, including wearing a purple suit and laughing insanely after absorbing Chill.

Alfred Pennyworth: Bruce Wayne's butler and oldest friend, Alfred serves in a near-identical capacity in this story. However, after Sinestro tampers with Bruce's power battery, Alfred sacrifices his life by taking the trap intended for his master.

Commissioner James Gordon: One of Batman's most trusted allies, Gordon is less trusting of Green Lantern because he holds so much power. In the end, he decides to help the Lantern, but is killed by Sinestro.

Harvey Dent/Binary Star: Dent is shown to be more supportive of Green Lantern than Commissioner Gordon. However, in his quest for allies, Sinestro gives him gauntlets that emit various forms of radiation that corrupt his mind, turning him into a supervillain in a similar fashion to Evil Star's Starband. In a nod to his more familiar appearance, Dent's face is half-darkened and he takes on the name Binary Star, complete with puns related to the number two.

Selina Kyle/Star Sapphire: Kyle is not explicitly named as this story's version of Star Sapphire, but several clues reveal her true identity. She carries a cat-o'-nine-tails, and Dent (as Binary Star) says she has "the eyes of a cat." Further, Bruce recognizes her from his first night of crimefighting, a nod to Batman: Year One.

Clark Kent, Diana, Barry Allen: These three superheroes apparently never began careers of their own; when contacted by the Guardians, Clark is shown at the Kent farm and Diana is still on Paradise Island. Each of them is given a power ring and becomes a Green Lantern, all of them wearing variations of their familiar costumes.

The Joker: The real Joker only appears in a handful of panels as the Red Hood, and never suffers the disfiguring accident that turned him into the Clown Prince of Crime. In an allusion to The Killing Joke, the unmasked Hood bears a strong resemblance to Alan Moore's version of the character, and, following his arrest, tells Green Lantern that he's "had a really bad day."

Multiverse
This Elseworld is part of Earth-32 of the 52 universes of the Multiverse. This character appears in Countdown: Arena #1-2. He and two other Green Lanterns fight against Monarch in the second issue.