MORE PHOTOS: 20th Annual Los Angeles Times Festival of Books @ USC

PHOTO BY JASON RZUCIDLO / ©AMERICAJR.com This fan asked Cryer if any ad-libbing was used in "Two and a Half Men."

PHOTO BY JASON RZUCIDLO / ©AMERICAJR.com

"No, that show was very tightly scripted," the actor answered. "We made it look like we were making it up. But it was scripted down to every syllable. I can only think of three lines that were improvised."

PHOTO BY JASON RZUCIDLO / ©AMERICAJR.com

Attendees passing by the USC Keck Medicine Health and Wellness Pavilion

PHOTO BY JASON RZUCIDLO / ©AMERICAJR.com

Over 150,000 people showed up for this year's Festival of Books

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"Find the Cutes" book

PHOTO BY JASON RZUCIDLO / ©AMERICAJR.com

It was written by Celestial Noot and illustrated by Vincent Noot