"Maybe not the worst of all time, but Julia Roberts in Michael Collins was super jarring. Her Irish accent was willy-nilly, and when it was on, it was still pretty terrible. Plus, she just looked out of place, like they dropped a supermodel into the middle of the Irish Civil War; you shove a big name and face like hers into a historical period piece like that, you're just asking for trouble. Should have went with an Irish actress."

—u/Horrible_Harry

"Mark Wahlberg in the Cary Grant role in the remake of Charade (The Truth About Charlie). The whole thing was a train wreck and a disgrace to everyone involved, save maybe Thandiwe Newton, but none of it was worse than Markie Mark in the male lead."

—u/Username_Chx_Out

"Maria Bello in the third Mummy movie, replacing Rachel Weisz. It would’ve been better to say Evelyn died than to recast her."

—Unknown

"The 'joke' about not being the same woman made me uncomfortable. They could have waited for Rachel Weisz, or simply had Evelyn be dead or preoccupied with a library, making it a guys' trip. I saw the film in theaters, but I haven't been able to bring myself to watch it again."

—Electrical-Turnip468

"She displayed no emotions and lacked any chemistry with the other lead character portrayed by Dane DeHaan, an actor I've never encountered in any other film. This is the worst casting decision imaginable."

—u/mimipie06

"I'm really frustrated with the casting decisions in this film, with the exception of Ethan Hawke. The filmmakers should have chosen actors who appear around 20 years older and can effectively deliver their lines. The cast looked too young to even have a driver's license, much less a pilot's license."

—u/CrayonPFish

"I doubt any casting decision could have salvaged that film, but I found it hard to believe for even a moment that Wahlberg was merely a goofy science teacher trying to make it through."

—u/crnelson10

"Who the @#&$ cast Topher Grace as Venom?! Seriously the kid's from That '70s Show. He's not scary at all. Especially when he was screaming in agony, I was just thinking to myself...'This is bad.'"

—u/glokazun

"Denise Richards trying to play a nuclear physicist in The World Is Not Enough — she was about as convincing of a nuclear physicist as a dog chewing on an atom-shaped chew toy."

—u/darth_hotdog

"His effort to mimic a British accent is absolutely comedic."

—u/brewshakes

"She's decent, but doesn't quite compare to DiCaprio and Daniel Day-Lewis."

—u/alienanimal

"Honestly, Daniel Day Lewis took his performance to a whole new dimension in that film. I recall seeing it as a child, and even back then, it felt like I was witnessing Leo, Cameron Diaz, and a guy who had time-traveled from the early 1900s. Leo and Diaz seemed to just be playing their usual selves, while Daniel Day Lewis completely transformed into his character."

—u/faislamour

"I just watched this movie like last week; her every emotion looked the same. The thing is, I like Kristen in the new Charlie's Angels (2019). I guess she just needs to find the right roles."

—u/depressedCucumbers

"After I saw some of her darker, edgier, more indie roles, I realized she's amazing when she's given room to be subtle. Her energy is very reserved but it's powerful. Personal Shopper (2016) is a strange movie that's one of my recent favorites for example — highly recommend it."

—u/Poppybiscuit

"He poses no threat at all — he appears to be stuck in a perpetual state of a 19-year-old college student still residing with his mom, so I can't see him as a sinister genius. No thanks."

—u/ILoveSnouts

"I genuinely appreciated his performance, but it doesn't align with the character of Lex Luthor. I would have preferred if they had introduced him as a different character, as I found his acting to be quite enjoyable."

—u/SS117_

"Sofia Coppola is a really talented filmmaker — as an actor, she just was not prepared for a role that big, in a movie that big. It's her father's fault for casting her at the last minute, and he admits it. Yes, everyone had their claws out ready to rip her performance, but even revisiting the movie, it's cringe-inducing. She just wasn't ready for all of that, and now that awkward performance is frozen in amber for generations to see."

—u/dystopika

"Robert De Niro as the young Frank Sheehan in The Irishman. There isn’t enough makeup and CGI in the world to make that work."

—u/Spindlebrook

"Absolutely, that was really foolish. No amount of CGI can replicate De Niro's ability to move and perform like a younger person. The whole 'de-aging' technique might be suitable for a brief flashback or a cameo appearance, but using it throughout an entire film takes away the opportunity from a younger actor who could have done the role much more effectively."

—u/Miserable_Reach9648

"Russell Crowe as Inspector Javert in Les Misérables. He just can't sing nearly as well as the other cast members — especially for a movie that is a musical."

—u/Fogel87767

"His performance as an actor was quite decent. However, the problem arose with his singing, which often felt out of sync compared to many of the other performers, particularly since he was paired with Hugh Jackman, a renowned musical theater star. It's acceptable to cast actors who may not excel in singing, but consistently placing them alongside those who do can emphasize the stark contrast in their skills, disrupting the audience's immersion. Since Javert serves as Valjean's foil, a direct comparison between the two characters is inevitable. Therefore, it's essential that both actors possess similar vocal abilities."

—u/megers67

"When it comes to Batman, he falls short. It's really not great. But I actually think he portrayed Bruce Wayne quite well. I feel similarly about Ben Affleck; he wasn’t the best Batman, but he nailed the Bruce Wayne persona. Both were hindered by terrible screenplays, yet they are talented actors at heart, just bogged down in the muck of subpar films."

—u/Oh_hi_doggi3

"Gwyneth Paltrow's portrayal of Tony Stark’s personal assistant who becomes CEO was truly disappointing. As someone with 30 years of experience in administration, I found her interpretation of the role to be a disservice to the profession."

—u/RedheadedCyclone

"During the pandemic, I dove headfirst into the MCU and found myself enjoying every bit of it. However, every scene with Pepper Potts felt a bit off to me. I appreciate her character's authenticity, but Paltrow's performance comes across as the most detached I've ever witnessed."

—u/Impossibleish