Can you imagine Danny Tanner on Full House being played by anyone other than Bob Saget? What about shy Wicca-to-be Willow Rosenberg on Buffy the Vampire Slayer not being Alyson Hannigan? Does your mind boggle at the thought of Sheldon and Leonard living across the hall from anyone but Kaley Cuoco as Penny on The Big Bang Theory? Well in all of those instances another actor was originally cast in that particular role, but was recast and replaced after the pilot. And those are not the only examples of sitcom and TV dramas switcharoos. In fact, it happens a lot more than you'd think.

Typically, before a concept is given the green light to go to full series, a pilot is shot first to give the network or studio a feel for what the show itself will look like. While in the pilot stage, several elements about the proposed series might change, from actors who aren't quite gelling with other cast members to even major plot overhauls that will alter the original idea, sometimes beyond recognition.

If you're curious to see what other characters from some of your favorite sitcoms and dramas (some of which date back quite a number of years) were originally played by someone else, check out our gallery to see some of our favorite TV show switcharoos.