As production stormed ahead for Batman and Robin in 1996, Warner were so impressed with the dailies that they greenlit another movie with Schumacher in the chair. The script was written by Akiva Goldsmith, who worked on Batman Forever and Batman and Robin. The plot would have bought back the cast and introduced The Scarecrow, played by Nicholas Cage. The plan was scrapped when Batman and Robin flopped at the box office and didn't return anything anywhere near the previous movies.
As 1998 rolled around, with Unchained officially scrapped, two scripts were made with plans to greenlight only one. The first script was a Joel Schumacher made adaptation of Year One and a live action adaptation of their latest hit cartoon, Batman Beyond. Neither project saw the light of day.
At the same time, comic fans Lee Shapiro and Stephen Wise had written a story based on Year One, called DarKnight, which would have seen an R-rated return to Batman, seeing a return of an older Batman who'd retired. Dick had gone to Gotham University and the villains would have been Scarecrow and Man-Bat. Scarecrow would have created Man-Bat and his murderous rampage would have framed Batman. However, the pitch and script were passed up in favour of Year One and Beyond.
Warner had already pitched the idea of having Chris O'Donnell return for a series of movies starring solo Robin, with his eventual change into Nightwing. This was confirmed in a 2012 interview with Chris, however, due to Batman and Robin flopping at the box office, these plans were scrapped.
By 2000, Warner had resurfaced with their Batman Beyond movie, which had been written by Paul Dini, Neal Stephenson and Boaz Yakin. Yakin was also in line to direct. However, Warner had gotten a script together with Frank Miller on making a Year One movie with Darren Aronofsky was set to direct. Once Yakin had turned in the script to Batman Beyond, the project was scrapped and Warner went ahead with it's greenlight on Aronofsky rebooting the Batman movie universe with Bale attached. However, once again, the project was scrapped due to Warner focusing it's efforts on Catwoman and a potential Batman vs. Superman movie.
The origins of Batman vs. Superman can be found in a 2000 pitch by J.J. Abrams called Superman: Flyby. The project was to be helmed by McG. McG dropped out to direct Charlie's Angels: Full Throttle. Wolfgang Petersen was lined up to direct Flyby, however the project was scrapped. In 2001, Andrew Kevin Walker had pitched a Batman vs. Superman movie with Petersen as director, Akiva Goldsman was attached to rewrite and in 2002, returned the pitch. The pitch was
"Bruce Wayne going through a mental breakdown after his five-year retirement from crime fighting. Dick Grayson, Alfred Pennyworth and Commissioner Gordon are all dead, but Bruce finds some solace in his fiancée, Elizabeth Miller. Meanwhile, Clark Kent is struggling because of a recent divorce from Lois Lane. Clark and Bruce are close friends, and Clark is Bruce's best man. After the Joker kills Elizabeth on their honeymoon, Bruce swears revenge, while Clark tries to hold him back. Bruce blames Clark for her death, and the two go against one another. Ultimately, Lex Luthor is revealed to have masterminded the entire plot to get Batman and Superman to destroy each other. The two decide to team up and stop Luthor"
Christian Bale was cited to play Bruce Wayne/Batman and Josh Hartnett was attached to play Clark Kent/Superman. This was the closest we actually got a Batman Vs Superman movie. Shooting was scheduled to commence in 2003, for a summer 2004 opening. Sadly, the project was scrapped in favour of the upcoming Superman Returns and Batman Begins.
As proof of how close the move was to completion, early promotion for the movie was placed inside the opening shot of I Am Legend, which features a billboard with the Superman logo inside the Batman logo. Akiva Goldman claims that this is an in-joke, but many fans don't believe so.