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.