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Batman & Robin (1997) More at IMDbPro »

The likely explanation is because it was so light and to a certain extent, campy in tone. This was a radical departure from how the other movies in the series had been made - the first two in particular were very dark and gothic, and even the third movie (also directed by Joel Schumacher) was darker than this one.

There are, of course, other reasons why fans and critics voice their displeasure at the film - the inclusion of nipples on Batman and Robin's suits and superfluous close-ups of their rear ends are frequent subjects of criticism, as is the use of various bad puns made by the character of Mr. Freeze, which all centered around an ice-related theme ("You're not sending me to the cooler!"). This was a great removal from the tragic undertones incorporated into his character in the early 90s that were almost universally accepted by fans (Though the backstory was still there, the campiness detached the audience from any true emotional connection). Fans were also upset over the depiction of Bane; whilst in the comics he is a very cunning strategist, in this film he is simply a mindless thug who might as well have been a generic goon.

The acting has also been widely regarded as bad and many of the actors (similarly to Val Kilmer's embarrassment at the previous Schumacher film) have admitted to not performing well in this film.

Freeze had only managed to find a cure for the disease in its earliest stages; his wife's case was too advanced for the treatment Freeze had found to be of any help to her. This is actually explained quite clearly in the film, yet this criticism frequently seems to pop up. While the script does contain many lapses in logic and continuity, this isn't one of them.

Not technically. While the events are often summarized in this fashion, the fact is that the film did not perform poorly in term of returns; it was actually one of the most profitable films of its year. However, critical reception from both reviewers and audiences was so sharply negative that it caused Warner Brothers to cancel the already-planned fifth film, to have been titled Batman Triumphant. The never-produced film, also to have been directed by Joel Schumacher, would've featured the Scarecrow and Harley Quinn as its villains, with a possible hallucinatory appearance by Jack Nicholson as the Joker. Feeling that the extreme backlash against Batman and Robin would result in future Batman films faring poorly, the franchise was put on the shelf for many years before Batman Begins restarted it with a completely new continuity.