It may have only taken ten years, but it looks like the playful rivalry between 'The Simpsons' and its sort of spiritual successor 'Family Guy' may finally be put to rest. While both FOX series have taken playful shots at one another over the years, the bridge has finally been built as 'Family Guy' creator and voice-artist Seth MacFarlane will lend his voice to an upcoming 'Simpsons' episode! Who might the golden-voiced 'Guy' play, and what does it have to do with 'Downton Abbey?'

We never thought we'd see the day, but Family Guy's Seth MacFarlane has officially crossed over to 'The Simpsons,' according to Entertainment Weekly. MacFarlane will appear in next fall's season premiere "Dangers on a Train," giving voice to the charming Ben, a married Man whom Marge accidentally connects with when she mistakes an "Ashley Madison" marital affair-type website for a cupcake-cake themed page. According to the report, much of their bonding comes from a mutual love of "Upton Rectory," a 'Downton Abbey' of sorts for 'The Simpsons.'

“We wanted to come together in a bipartisan way to make Fox Sunday night rock,” says 'Simpsons' executive producer Al Jean of the casting. “This was all very fun.”  Don't think MacFarlane would appear on 'The Simpsons' without showcasing his singing voice as well, as the future Oscar host will get to perform a rendition of "The Way You Look Tonight." And did we mention comedian Lisa Lampanelli will play MacFarlane's wife?

The humor won't end there, as Jean notes that the two rival series will put aside their differences to take mutual aim at FOX, MacFarlane's character at one point quipping "There’s so much great stuff on Sunday nights...except on FOX.”

MacFarlane also noted that the future could certainly hold room for 'Simpsons' stars to guest on 'Family Guy' as well, though nothing official has been set. What say you?  Are you excited to see worlds collide when Seth MacFarlane lends his voice to 'The Simpsons?'

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