Big Bang EPs Reveal Roles That Almost Went to Selena Gomez, Sandra Bullock, Macaulay Culkin and Ringo Starr

Can you imagine a version of The Big Bang Theory where Leonard was played by someone other than Johnny Galecki?

The new book The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series by Jessica Radloff (order it here) not only reveals the four well-known actresses who read for Penny, but the former child star who met with producers about playing Dr. Hofstadter. It’s among more than a dozen casting secrets exposed in the 500-page oral history — from the eventual series regular who was forced to forfeit the part of Howard, to the music icon who was approached about bringing Howard’s absentee father to the screen.

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The tell-all also discloses which character was almost recast after the 2007 pilot, which cast member thought they’d have to quit ahead of Season 5, and the role that could’ve gone to Big Bang superfan Selena Gomez if only she’d had the time. Scroll down for all those answers and more, then hit the comments and tell us which of the book’s many revelations took you most by surprise.

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