Christian Bale

When the Bat-Signal lights up the sky, it can only mean one thing: a new "Batman" movie is on the way. It’s a moment of celebration as fans rejoice after seeing the Dark Knight on screen one more time while the Internet complains about why Bat-Mite hasn’t received his own trilogy yet. Who knows — it might still happen, considering the obscure character is canon in the DCEU now.

Despite the glee that Batman brings us as he knocks some sense into Gotham City’s underworld, the stories behind these blockbuster productions are often as fascinating as the action and drama on display. Whether it was the hush-hush secrecy around Tim Burton‘s "Batman Returns," Danny DeVito’s Penguin getting attacked by a monkey, or Robert Pattinson freaking out Warner Bros. with his joyride in the Batmobile, there always seems to be some bizarre tale that makes headline news. With that said, let’s head back to the Batcave and dig through the Batcomputer’s archives to discover the strange things that happened on "Batman" movie sets.

The time Batman needed a nap

Bruce Wayne sleeping

It must be tough being both Bruce Wayne and Batman. Imagine having to put on the front of being a socialite playboy during the day, then hitting the streets to kick in some skulls and defend Gotham City’s honor at night. Seriously, when does he find the time to get some shuteye and dream about unleashing vengeance on a new batch of criminals? After all, the CDC recommends a solid seven hours per night, and it appears as if Batsy isn’t taking the advice to heart.

As it turns out, it’s grueling for actors who work long hours on film sets as well. Just ask Christian Bale. In conversation with GQ, he revealed that he falls "asleep on sets all the time." In fact, he had an embarrassing moment on the set of "Batman Begins" where his co-stars Michael Caine and Morgan Freeman saw him snoozing away. "In the scene, I was meant to be waking up, so I laid down and just fell asleep," Bale told the outlet. "And I didn’t hear ‘Action.’ So Michael and Morgan were talking, and I was supposed to join in. I woke up with Michael Caine poking me in the ribs and going, ‘Look at ‘at! ‘E’s bloody fallen asleep, ‘asn’t ‘e ‘E’s bloody fallen asleep!" He probably would have been even comfier if he had his Bat PJs on.

The Cat strikes

Catwoman riding the Batpod

Considering how action-packed "Batman" movies are, it shouldn’t come as any surprise that the occasional accident will happen on set. Most people would expect a stray punch, a pebble in the shoe, or even a broken window or two, but damages of up to $500,000? Well, that’s how much IMAX cameras are insured for, according to Premium Beat, and Christopher Nolan and his team have totaled at least three of them over the years.

Warner Bros. execs must have been pulling their hair out when the news broke that a Catwoman stunt double crashed into an IMAX camera on the set of "The Dark Knight Rises," per TMZ. While there was an initial denial that the camera was damaged in the accident, the footage from the incident suggested otherwise. Thankfully, the stunt double and cameraman weren’t hurt in the process. The insurance company, on the other hand, must have been hurting from that sizable payout. Not quite chump change, is it?

Batman almost didn’t begin

Bruce Wayne fighting Henri Ducard

Remember the scene in "Batman Begins" where Henri Ducard (Liam Neeson) trained Bruce Wayne (Christian Bale) on the ice? After numerous losses to Ducard, Bruce eventually defeats him, only to fall into the freezing water, essentially serving him the lesson to not become too overconfident in a fight. While it was a good piece of movie magic since the actor wasn’t required to submerge himself in sub-zero temperatures (otherwise, he wouldn’t be around anymore), there was a danger in filming everything else that came before it. In fact, it was one of the first filmed scenes of the production and could have ended up being the last, as per a report in the Chicago Tribune.

The scene was filmed in Iceland, and the weather wasn’t exactly bursting with a mojito-on-the-beach vibes. The glaciers, though, were a far more chilling factor for the cast and crew. "We were out there, and it was splitting — there were big cracks appearing down it — and we all had to stand still and not break it," Bale explained to the Chicago Tribune. "By the next day, there was all this water again." The question is, did anyone ever consider pulling out the ice skates and creating an honorable tribute to the infamous skate-fight scene from "Batman & Robin"?

Bon Jovi’s gift for Batman & Robin

Jon Bon Jovi with his arms spread

The casting of Arnold Schwarzenegger as Mr. Freeze in "Batman & Robin" was a peculiar one, especially since there was a pesky rumor that Patrick Stewart had originally been up for the role (via Entertainment Weekly), and he made far more sense as the cerebral and damaged Dr. Victor Fries than Arnie. At the same time, Schwarzenegger’s icy puns and cool play on words didn’t come cheap, as he cost the production a chilling $25 million (per The Hollywood Reporter).

As the biggest star on set, it was no surprise that Schwarzenegger attracted a lot of attention, and he even had a few high-profile friends stop by the production every so often. "Jon Bon Jovi came by, and he brought Cuban cigars for Arnold," actor Stogie Kenyatta told The Hollywood Reporter. "So Arnold had them color it white so he could smoke it in the scenes." Fortunately, Bon Jovi only contributed cigars and not a song to the movie, as that pleasure went to the Smashing Pumpkins, who delivered the Grammy Award-winning track "The End Is the Beginning Is the End" — arguably, a much better song than anything Bon Jovi would have supplied to the soundtrack.

Robin’s mask was a sticky problem

Robin suit from Batman & Robin

On the surface, Chris O’Donnell’s Dick Grayson/Robin should have had an easier time in costume than the other half of the Dynamic Duo. He didn’t require the complex Batsuit — which was a notorious issue for Batman actors (via The Guardian) — and only had a domino mask to conceal his identity (an incredibly laughable concept in the same vein as Clark Kent’s glasses disguise, but that’s an issue for another time).

But it wasn’t as simple or comfortable as that, according to O’Donnell. "First thing in the morning, they painted my eyes black and then would glue the mask on [to my face]," he said to Entertainment Tonight. "It was so hot, you would touch the mask, and water would just run down your face." O’Donnell added that the "Batman Forever" suits were also difficult to take off and put on, so he and Val Kilmer stayed in costume for most of the time. Fortunately (for everyone’s bladders), costume adjustments were made for the sequel, "Batman & Robin."

To be fair, though, his time as Robin was a walk in the park compared to Burt Ward’s run. At least he didn’t have to wear extra-small green shorts and pixie boots, though he was still cursed with the infamous Bat-nipples.

Robert Pattinson’s worst day

Robert Pattinson filming The Batman

For anyone playing Batman, it’s a lot of pressure. Not only will there be debate among the fanbase if someone is the right choice or not, but there’s also the difficulty of acting with a cowl that covers most of your face and makes it incredibly difficult to see emotion. Robert Pattinson found out about this challenge first hand, as "The Batman" director Matt Reeves insisted he redo a specific scene over and over again, as per Insider. From Pattinson’s perspective, however, he couldn’t see what he was doing wrong until Reeves called him over to see the issue with the shot. In fact, Reeves told Insider he believed the actor "was about to burst a vein" at one point.

"That was maybe the worst day of the whole shoot because I really genuinely thought it was [Reeves] that was wrong," Pattinson told the outlet. "I was like, how can we be doing 40 takes of this?" While that does sound excessive, The Sun reported that Pattinson had to redo a scene 50 times. Whether it was the same scene or not is unclear, though that’s more than enough to drive anyone a little batty.

The Penguin vs. The Monkey

A monkey wearing a suit and holding a note

Working with animals can be a challenge since they don’t always stick to the script. It’s already been covered how the penguins in Tim Burton’s "Batman Returns" behaved like divas, but no one expected the spider monkey to misbehave as it did on set. Danny DeVito described his experience with his furry co-star as "horrifying" on "The Graham Norton Show."

Explaining the situation to Norton and his guests, DeVito revealed how the monkey was meant to come and deliver a note from Batman to his character, the Penguin. The crew tested the scene with the animal trainers beforehand, and everything went according to plan. However, when DeVito called the monkey over, things went — ahem — south. "The monkey comes down, takes one look at me, and leaps at my balls," the actor said, adding that his costume was heavily padded, so he was fortunate enough to not feel the bite (though he did see the chunk missing on his suit). DeVito wasn’t left too shaken by the incident as he did another take, which proved to be more successful (and filled with less monkey fury) the second time around.

The shoving match between star and director

Joel Schumacher showing the peace sign

Superman and Lex Luthor. Batman and Joker. Joel Schumacher and Val Kilmer?! Despite working together on "Batman Forever," there was no love lost between director and actor by the time the film hit theaters. In fact, Schumacher told Vulture: "I didn’t say Val [Kilmer] was difficult to work with on ‘Batman Forever.’ I said he was psychotic." Talk about not holding back any punches here.

Schumacher explained to Entertainment Weekly that he’d heard stories about Kilmer’s behavior in the past, but he decided to hire him to play Batman anyway since he thought he was an excellent performer and right for the role. However, their relationship became patchy after a few weeks of production, and Kilmer’s actions towards the rest of the crew rubbed him up the wrong way. Schumacher told Entertainment Weekly that they "had a physical pushing match," as he called the actor "badly behaved," "rude," and "inappropriate." After their encounter on set, Kilmer didn’t speak to the director for two weeks — a period that Schumacher described as "bliss." Kilmer didn’t return for "Batman & Robin," but neither Warner Bros. nor Schumacher seemed to be too broken up about it.

Fake names to get on set

Tim Burton behind the scenes of Batman Returns

When Tim Burton’s "Batman" raked in over $411 million at the box office (via Box Office Mojo), Warner Bros. started to get a little more protective over its investment. No longer was it a comic book movie made purely for children; it was now a global franchise with huge earning potential. As a result, the studio took some extreme measures when it came to protecting the integrity and secrecy of the sequel, "Batman Returns," as per Entertainment Weekly.

The cast and crew were given ID badges for a fake movie title called "Dictel." These badges were absolutely necessary for them to get around on set, as the studio tried to prevent prying eyes from visiting the production unannounced. That wasn’t all, though, as the poor art directors had to shut out the sun and pull down the blinds in their office. Sure, they were working on a film called "Batman Returns," but did they really have to operate like bats in the darkness? Nowadays, leaks happen all the time, and studios don’t seem to be too overly concerned about them.

Pattinson’s joyride in the Batmobile

Batmobile from The Batman

Imagine being cast as Batman and trying on the cape and cowl for the first time. As Robert Pattinson told Variety, it’s a "transformative" experience. Once the Batsuit is on, though, what’s next on the list? Getting behind the wheel of the Batmobile, of course.

Much like anyone else in his shoes, Pattinson was excited to take the Batmobile for a spin around the block when he received the keys. However, his eagerness ended up causing a few frowns, as he explained to Empire Magazine (via Syfy Wire). "They wanted me to drive it, like, only 10 feet, but I immediately went off for 25 minutes, trying do all the stunts I’d learned in the normal cars," he said. "After that, I was never allowed to drive it without someone else in the car." Hopefully, Pattinson had a GoPro on him, and the footage of him raging through the streets in the Batmobile finds its way online soon because that would be the best kind of behind-the-scenes material that we all deserve. Fingers crossed.

The aliens are coming

The Tumbler version of the Batmobile

After the sleekness and over-the-top appeal of the previous Batmobiles, the Tumbler was a major departure for "Batman" movies. Big, bulky, and looking more like a battle tank that swallowed another smaller tank, it took a while to get used to. However, once everyone saw the practicality and logic behind it, it made a lot more sense and has gone on to become one of the best non-comic Batmobiles.

The Tumbler’s toughness was put to the test on the streets of Chicago during the shooting of "Batman Begins." As Christian Bale explained at WonderCon 2005 (via Groucho Reviews), the vehicle took everyone’s breath away, but it also frightened one driver in particular. "There was even this guy who crashed into it," Bale said. "This poor drunken guy who didn’t have a license, who said he got so panicked when he saw the car, he thought aliens were landing." Look, if it had been the Batmobile from "Batman Forever," the excuse of thinking it was an alien would be far more plausible since it had an otherworldly quality, especially with the lights on the side.

Breaking the ice

Arnold Schwarzenegger as Mr Freeze

A lot has been written about the difficulties of wearing the various Batsuits, but what about the villains? While Cillian Murphy wore a potato sack over his head for Scarecrow and Paul Dano slipped into a sexy green number for the Riddler, it pales in comparison to what Arnold Schwarzenegger had to go through to turn into Mr. Freeze.

At first, the star was willing to shave off all his hair for the role, as per The Hollywood Reporter; however, he had a change of heart and requested a bald cap in the end. That wasn’t the biggest challenge for Freeze’s look, though, since the LED lights for his mouth caused some concern for him and the crew, as revealed by "Batman & Robin" makeup artist Jeff Dawn. Not only was it an obstruction for him delivering his lines, but it also brought with it another major hazard. "When you put it in Arnold’s mouth, Arnold’s saliva would creep into the seams of this thing and attack the batteries," Dawn told The Hollywood Reporter. "The batteries would immediately start disintegrating and start putting out battery acid into Arnold’s mouth." Licking battery acid is never a good idea, and before Schwarzenegger could say "hasta la vista" to the production, the makeup team figured out a quick solution: putting the device into a balloon. Now, that’s cool.