In the world of Hollywood, every walking moment of our favorite celebrities' lives is scrutinized. Brad Pitt can't even wander down to his local Starbucks for a calorie-heavy Unicorn Frappuccino without being bombarded by swarms of paparazzi, and Emma Stone, if you think you can go for a light morning job without running into squealing fans, think again.

Some A-listers are sly and cunning when it comes to dealing with the constant onslaught, able to take any criticism on the chin and move on. Flipped, however, a handful of celebs take it one (or many) steps too far, losing their cool and belittling their fans, co-stars, and even assistants.

Grab the popcorn, turn on the volume, and let's take a look at these 20 Hollywood stars who seriously lost their chill.

20 Christina Aguilera

On the big screen, we saw Christina Aguilera turn heads in films like Burlesque. What we didn't see, however, is what happened behind the scenes. Not only has the singer been notably rude toward fellow celebrities Valerie Bertinelli, Adam Levine, and Kelly Osbourne, but she's also heartlessly shunned away fans who have tried to interact with her.

19 Alec Baldwin

Time and time again, we've seen the great Alec Baldwin find himself in some sort of hot water. Over the years, the 30 Rock star has gotten into fights with photographers, been taken into custody for beating someone up, and never been afraid to arc up to pushy fans. Folks, don't poke the bears.

18 Justin Bieber

Over the years, it's always been tough for Justin Bieber to escape the spotlight. So, unfortunately for him, even his more embarrassing moments are captured by the paps and scrutinized by the wider public. One of his more notable, regrettable moments was when the singer spat on fans from the balcony of his Toronto hotel room.

17 Robert Pattison

While Robert Pattinson is still certainly a household name, his status and fame peaked when he was thrust into the role of Edward Cullen in the Twilight series. During the saga, because he didn't particularly like the character he was playing, he made it very clear how he felt about fans who loved Edward Cullen with a passion - and it wasn't good.

16 Sandra Bullock

From Miss Congeniality to The Blind Side and Bird Box, Sandra Bullock has no shortage of blockbuster hit films. However, on a less proud note, she also has a track record of publicly belittling her fans. In 2012, she apparently yelled at a wheelchair-bound fan, and subsequent rumors of poor behavior have followed.

15 Christian Bale

We saw Christian Bale in the Batman films and we absolutely loved him, right? Sure. But you know who wasn't the biggest fan of his work? The obsessed fan who Bale suggested should be “eliminated.” Plus, there have also been reports that he's sent girls away from his table at restaurants in tears after they asked for a photo.

14 Gwyneth Paltrow

While we're all too familiar with our dear Gywneth these days thanks to her recurring role as Pepper Potts in the industry-dominating Marvel Cinematic Universe, there's a lot more to the story, and it's not all positive. She has constantly belittled people who don't earn massive paychecks, which, to be fair, is  most of her fanbase

13 Katherine Heigl

After she dominated the small screen with her Emmy award-winning recurring role on the hit drama Grey’s Anatomy, Heigl, potentially accidentally, went ahead and offended all the fans of the show. She asked for her work not to be considered for future awards, stating bluntly that the show wasn't as good as it used to be.

12 Jared Leto

Aside from being a real pain in the backside and pissing off his costars during the production of Suicide Squad, Jared Leto has also managed to alienate fans over the years with his questionable - to put it nicely - behavior. He's lashed out at concertgoers, flipped the bird, and made fun of a fan for not knowing the words to his songs.

11 Rihanna

We all know and love Rihanna for her industry-leading work and chart-topping hits. What's been cleverly swept under the rug, however, is an incident that involved a 16-year-old girl. In essence, the girl wore an outfit inspired by Riri, only for it to be thrown back in her face on social media.

10 Tobey Maguire

If you were hoping to snag an autograph from the original Spider-Man, you might want to reconsider. Autograph Collector magazine has ranked him as the absolute worst celebrity to try to approach, saying that he’s "so wrapped up in his own egotistical web that he has earned the distinction of being the worst signer of the year."

It's official, folks, the original Spider-Man actor is the absolute worst celebrity to try to approach for a quick scribble. In specific events, he's slapped a phone out of a hopeful fan's hands who was just trying to get a selfie. Get your act together, Tobey.

9 Bruce Willis

Bruce Willis might be one of Hollywood's leading action men, but he's supposedly one of Hollywood's rudest men as well. Aside from his persistent reputation for having a negative attitude, there was a specific incident back in 1996 in which Willis yelled at a group of boys interrupting his lunch.

8 Lucille Ball

We're throwing it way back to the days of I Love Lucy, where the leading lady, Lucille Ball, continually created a lovable on-screen persona. Off the screen, however, it was another story entirely. Whenever she would be approached by fans, instead of interacting like a normal human, she made her assistant speak for her instead.

7 Russell Crowe

With roles in everything from Gladiator to Les Miserables, it's hard to deny the fact that Russell Crowe is a talented, versatile actor. While he's well-known for his on-screen roles, he's equally known for his short temper and violent outbursts. On The Late Late Show in 2015, for example, he told the entire crowd to ‘shut up’.

6 Jennifer Lopez

What do you do when a maid is secretly a fan and asks you for an autograph? Well, if you're J-Lo, then you fire her on the spot, apparently. The infamous performer's rap sheet stretches far further than that as well, with many reporters claiming that Jenny from the block was a nightmare to have an interview with.

5 Chevy Chase

Thanks to the beloved sit-com, Community, and the National Lampoon movies, Chevy Chase developed a friendly, positive on-screen persona. When the cameras weren't rolling though, it was another story. There have been a number of critical fan comments over the years, and even Will Ferrell can't stand him, calling Chevy the worst SNL guest host in the show's history.

4 Cameron Diaz

If a celebrity with over 20 years of experience wanted to turn down an interview request every once in a while, we'd understand - they're probably extremely sick of it. The former Charlie's Angel takes it to another level - Diaz actually berates fans about why asking for autographs is ridiculous, and for that reason, Autograph Collector magazine ranked her as one of the worst.

3 Catherine Zeta-Jones

It’s no surprise that many young women want to emulate Catherine Zeta-Jones. However, when one 8-year-old fan told Zeta-Jones that she wanted to be an actress, she was left completely devastated. The girl recalled the awkward moment years later: “She turned to me, looked me up and down, and said ‘You’re pretty enough, I suppose,’ then went back to her conversation… I went from feeling at ease in the world to constantly thinking about how everyone was judging me on my appearance.”

2 Hilary Duff

Lizzie McGuire herself might be all smiles and rainbows on screen, but there's a darker side that we haven't been fully exposed to just yet.  Although not a blatant diss, she did manage to piss off a significant number of Native American when she dressed up as a sexy pilgrim for Halloween. Not the smartest choice, Hilary.

1 Spike Lee

From journalists to fellow creatives and fans, we've heard plenty of reports of Spike Lee's cold attitude and poor demeanor. One particular event caused a bit of a ruckus with his fans - when giving a public lecture at a University, he was dismissive to eager audience members who wanted to ask him questions, considering shrugs and eye rolls as appropriate responses.

Sources: Looper.com, Vanityfair.com, Newsweek.com

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