MacFarlane, who is to serve as host of the Oscars in February, will appear in the 25th season premiere of "The Simpsons" next fall, the New York Daily News reported.
MacFarlane will play a married man who romances Marge Simpson online after learning they both share a passion for the "Downton Abbey-esque" show "Upton Rectory," "The Simpsons" producer Al Jean told Entertainment Weekly.
Dan Castellaneta, who does the voice of Homer Simpson, recently guest-starred on a "Family Guy" episode, the Daily News said.
Both "The Simpsons" and "Family Guy" air on Fox.
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