Paul Shaffer was offered the role of George Costanza on "Seinfeld."
According to The Week (by way of Shaffer's memoir), Jerry Seinfeld offered Shaffer the role of George with a message on Shaffer's answering machine, but Shaffer never returned the call. It certainly would've made for a very different "Seinfeld."
The Week also reports Ken Howard and Blythe Danner were originally offered the roles in NBC's "McMillan and Wife," but turned them down because they weren't interested in being part of the "wheel" format of NBC's mystery series. The parts went to Rock Hudson and Susan St. James.
Did you know that Matthew Broderick and John Cusack were up for the lead on "Breaking Bad" before Cranston got the job?
Click through the slideshow below to see what other famous faces turned down some pretty big roles.