Several actresses were reportedly in consideration for Harley Quinn before Margot Robbie caught the attention of studio executives. Once she was in the running, there wasn't much debate, she committed fully to the role and made it entirely her own. Her take on Harley Quinn became one of the few elements of Suicide Squad that fans and critics agreed on, and it launched a whole new chapter for the character in the DC universe. | © Warner Bros. Pictures
Lindsay Lohan originally wanted to play Regina George, and Amanda Seyfried also auditioned for the role before Rachel McAdams landed it. McAdams made Regina so watchable and so precisely awful that it's easy to forget the part could have gone to someone else entirely. She turned a high school villain into one of the most quoted characters in early 2000s comedy, and the casting ended up being just about perfect. | © Paramount Pictures
The role of Tris Prior was highly sought after, with plenty of young actresses in the running before Shailene Woodley secured the part. She brought a balance of vulnerability and toughness to the character that gave the franchise a solid emotional core. It was the kind of role that required carrying an entire film series, and Woodley proved she was up to it. | © Lionsgate Films
James Cameron had his pick of established names for the lead role in Avatar, with Matt Damon among those considered for the part. He ultimately went with Sam Worthington, who was a relatively fresh face in Hollywood at the time. The film went on to become the highest-grossing movie ever made, which is a pretty remarkable outcome for a casting decision that could have gone in a very different direction. | © 20th Century Studios
The casting search for Marvel's new Spider-Man was a long one, with a wide pool of young actors being considered for the part. Tom Holland eventually landed the role and brought something to it that previous versions hadn't quite nailed, a Peter Parker who actually felt like a nervous, eager teenager trying to figure things out. The gamble on a relatively unknown young British actor paid off in a big way for the franchise. | © Walt Disney Pictures
Director Nick Cassavetes was specifically looking for someone he didn't consider conventionally attractive for the role of Noah, which makes it all the more ironic given what happened next. Ryan Gosling got the part and ended up becoming one of Hollywood's most recognized romantic leads off the back of it. The chemistry he built with Rachel McAdams on screen turned The Notebook into a cultural touchstone that people are still talking about twenty years later. | © New Line Cinema
Director James Gunn wasn't even planning to audition Chris Pratt initially, seeing him mostly as the goofy guy from Parks and Recreation. A long list of other actors was considered before Pratt eventually got in the room and won Gunn over. He turned out to be such a natural fit for the role that it's genuinely difficult to imagine Guardians of the Galaxy working the same way with anyone else. | © Walt Disney Pictures
Julia Roberts was reportedly offered the role of Leigh Anne Tuohy first and turned it down. Sandra Bullock took it on instead and delivered what many consider the defining performance of her career. She won the Academy Award for Best Actress for the role, which makes Roberts' pass one of the more notable missed opportunities in recent Hollywood history. | © Warner Bros. Pictures
Katie Holmes originated the role of Rachel Dawes in Batman Begins but chose not to return for the sequel. Maggie Gyllenhaal took over for The Dark Knight and brought a different kind of presence to the character: more grounded and assured than the original take. Stepping into an established role mid-franchise is never easy, but Gyllenhaal held her own alongside Christian Bale and a scene-stealing Heath Ledger. | © Warner Bros. Pictures
Dougray Scott was originally cast as Wolverine, but had to drop out when his schedule on Mission: Impossible 2 ran over. Hugh Jackman, relatively unknown at the time, stepped in as a last-minute replacement. He ended up playing the character across nearly two decades and multiple films, turning what started as a scheduling conflict into one of the most iconic casting fits in superhero movie history. | © Walt Disney Pictures
Anne Hathaway was originally attached to the role of Tiffany Maxwell, but creative differences led to her exit from the project. Jennifer Lawrence stepped in and delivered a performance that felt so natural and lived-in, it's hard to picture the film without her. She took home the Academy Award for Best Actress for the role, making it one of the more consequential last-minute casting switches in recent Hollywood history. | © The Weinstein Company
Edward Norton played Bruce Banner first in The Incredible Hulk, but when Marvel started assembling the team for The Avengers, they decided to make a change. Mark Ruffalo stepped into the role in 2012 and brought a warmth and relatability to Banner that clicked immediately with audiences. What started as a recast turned into one of the most popular versions of the character the franchise has ever had. | © Universal Studios
When Pierce Brosnan stepped away from the Bond franchise, the search for a replacement was wide open, with Henry Cavill among those in consideration. Daniel Craig wasn't exactly the crowd favorite going in; there was real skepticism about whether he could carry the role. One viewing of Casino Royale put that debate to rest pretty quickly, as Craig's grittier, more grounded take on Bond gave the franchise a shot of energy it badly needed. | © Sony Pictures Releasing
Rachel McAdams was the original first choice for the role of Andy Sachs, but she passed on it, opening the door for Anne Hathaway. Hathaway went after the part and ended up delivering a performance that's hard to picture anyone else pulling off, especially opposite Meryl Streep. It's one of those happy accidents in casting where the backup plan turned out better than the original. | © 20th Century Fox
Christina Applegate was among the actresses considered for the role of Elle Woods before Reese Witherspoon came into the picture. It's one of those casting decisions that's hard to imagine going any other way now, given how completely Witherspoon made the character her own. Elle Woods became one of the most beloved heroines in early 2000s cinema, and a lot of that comes down to the specific energy Witherspoon brought to the part. | © 20th Century Studios
Not every iconic performance was the original plan. These roles almost went to completely different actors, and the castings we ended up with changed Hollywood forever.
