Batman Unchained was the planned sequel to Batman & Robin. The script was written by Mark Protosevich and Joel Schumacher was signed to direct it. It was cancelled after the negative reception of Batman & Robin. Some themes from this script were later used in Batman Begins.
- George Clooney as Bruce Wayne/Batman
- Nicolas Cage or Jeff Goldblum as The Scarecrow
- Courtney Love or Madonna as Harley Quinn (Joker and Alicia's daughter)
- Chris O’Donnell as Dick Grayson/Robin
- Alicia Silverstone as Barbara Wilson/Batgirl
- Michael Gough as Alfred
- Pat Hingle as Commissioner Gordon (expected)
- Cameos by Jack Nicholson, Michelle Pfeiffer, Danny DeVito, Jim Carrey and Tommy Lee Jones during a hallucination scene during the finale.
During the filming of Batman & Robin, Warner Bros. was impressed with the dailies. This prompted them to immediately hire Joel Schumacher to return as director for a sequel, but writer Akiva Goldman, who worked on Batman Forever and Batman & Robin with Schumacher, turned down the chance to write the script. In late 1996, Warner Bros. and Schumacher hired Mark Protosevich to write the script for a fifth Batman film. A projected mid-1999 release date was announced. Titled Batman Unchained, Protosevich's script had the Scarecrow as the main villain. The Joker would return as a hallucination in Batman's mind caused by the Scarecrow's fear toxin. Harley Quinn appeared as a supporting character, written as the Joker's daughter trying to get revenge on Batman for the Joker's death. George Clooney and Chris O'Donnell were set to reprise the roles respectively. However, when Batman & Robin received negative reviews and failed to outgross any of its predecessors, the idea was to bring Tim Drake in the Bat Picture but Warner Bros was unsure of their plans for Batman Triumphant and George Clooney vowed never to wear the cape and cowl again. Director of the previous two films Joel Schumacher stated in a documentary that he turned down the chance to return stating that he lost his passion for Batman in film and didn't want to turn the passion into just a job.
The studio decided it was best to consider a live-action Batman Beyond film and an adaptation of Frank Miller's Batman Year One. Warner Bros. would then greenlight whichever idea suited them the most. Schumacher felt he owed the Batman culture a real Batman movie. I would go back to the basics and make a dark portrayal of the Dark Knight." He approached Warner Bros. of doing Batman: Year One in mid-1998.