Gillian Anderson as Lady Cora on Downton Abbey
Can you imagine Agent Scully residing in Downton Abbey? It almost happened, but the X Files star turned down the role that eventually went to Elizabeth McGovern.
Ashlee Simpson as Elena on The Vampire Diaries
It's hard to imagine anyone else playing Elena Gilbert on the CW hit series, but the singer-actress was the network's first choice. It wasn't until the producers took a second look at Nina Dobrev's audition tape that they decided to go with the Bulgarian beauty.
Whitney Houston as Sondra on The Cosby Show
The legendary singer was offered the lead role in Bill Cosby-led series, but passed to pursue her music career.
Dana Delany as Carrie on Sex and the City
To Sex and the City fans, Sarah Jessica Parker is Carrie Bradshaw, but once upon a time, Dana Delany was offered the role of the New York columnist. The Emmy-winner passed because she had already done multiple projects involving x-rated material (Nude Girls, Exit to Eden) and didn't want to be involved with a project that had "sex" in the title.
Paul Schaffer as George on Seinfeld
David Letterman's bandleader was offered the role by Jerry Seinfeld without an audition, but Shaffer never called him back.
Thomas Jane as Don on Mad Men
AMC wanted Jane as Don Draper, but Jon Hamm said during a podcast that Jane passed because he didn't want to be on a television show. Of course, he would go on to star in HBO's Hung.
Ryan Reynolds as Xander on Buffy the Vampire Slayer
2010's Sexiest Man Alive could have been part of the Joss Whedon crew, but he passed on the role of Xander. "I love that show and I loved Joss Whedon," he told The Toronto Star in 2008. "But my biggest concern was that I didn't want to play a guy in high school."
Scott Foley as Ted on How I Met Your Mother
Haaave you met Scott? The Scandal star reportedly auditioned for the main character in the CBS hit comedy. Maybe he'll land a role in the spinoff?
Isaiah Washington as Derek on Grey’s Anatomy
Ellen Pompeo revealed to the New York Post that creator Shonda Rhimes wanted Isaiah Washington to play McDreamy. "Shonda really wanted to put a Black man in the mix. I didn't think they were really going to put an interracial couple on the show and I didn't want him. It was too close to home," she said, referencing her own marriage to music producer Chris Ivery. "I said I wanted that Dempsey kid."