<START> 'Simpsons' characters to appear on 'Family Guy' Creator and Executive Producer Matt Groening, Nancy Cartwright, the voice of Bart Simpson and Dan Castellaneta, the voice of Homer Simpson (L-R) sign posters at the unveiling of the new "The Simpsons" U.S. postage stamps in Los Angeles May 7, 2009. LOS ANGELES, July 19 (UPI) -- American television network Fox has announced plans for a crossover event featuring the animated characters of "The Simpsons" and "Family Guy." The special "Family Guy" episode will see Peter and the rest of the Griffin clan heading to Springfield where they'll encounter Homer, Marge, Bart and Lisa Simpson, TVGuide.com said Thursday. The show -- in which the iconic characters meet for the first time -- is to air in the fall of 2014, the report said.