Robin

Robin was a spin-off film to Batman and Robin, but was cancelled due to the critical and box office failure of the 1997 film.

Plot
The plot is for the most part unknown. It would likely focus on how Robin became Batman's sidekick.

Why It Was Cancelled

 * 1) Batman and Robin flopped at the box office and received extremely negative reception from critics, audiences and fans of Batman (mentioned earlier).

Result

 * Robin was permanently cancelled.