Cesar Millan's television show Dog Whisperer on National Geographic debuted in 2004, but Millan previously spent years struggling to pursue a career as a dog trainer. Robin Layton/Courtesy of Cesar Millan hide caption

itoggle caption Robin Layton/Courtesy of Cesar Millan

Over the course of Breaking Bad, Walter White (Bryan Cranston) metamorphosed from a high school chemistry teacher to a notorious outlaw. Ursula Coyote/AMC hide caption

itoggle caption Ursula Coyote/AMC

Mike Birbiglia started his career as a server and fill-in comic at a comedy club in college. Charles Sykes/Invision/AP hide caption

itoggle caption Charles Sykes/Invision/AP

Neil deGrasse Tyson is hosting Cosmos, the science documentary series made popular by Carl Sagan. Tyson is Sagan's successor as America's most famous scientist. Richard Shotwell/Richard Shotwell/Invision/AP hide caption

itoggle caption Richard Shotwell/Richard Shotwell/Invision/AP