Bittersweet though it may be, 'Futurama' will finally return tonight for the first of the final 13 episodes, beginning with "Fry and Leela's Big Fling." While we've learned of some impressive genre guest stars to debut in the coming weeks, most surprising of all is that 'Family Guy' creator Seth MacFarlane will lend his voice to the futuristic animated comedy, and you'll never guess as whom!

According to Entertainment Weekly, MacFarlane will voice the role of Fry's dog, Seymour, during an Aug. 14 episode, in which the Planet Express crew ventures into Fry's dreams for a mission to the year 1999. Comedian Sarah Silverman will also reprise her role as Fry's ex-girlfriend, Michelle, for the episode.

Says Executive Producer David X. Cohen of the guest stint:

This will be Seymour’s first and only spoken dialogue. Since Seth voices 'Family Guy''s talking dog, Brian, we thought it would be funny to have him blatantly rip himself off for our benefit. As an added bonus, the only person he can sue is himself, so we’re off the hook.

This will mark the second occasion this year in which MacFarlane has crossed over animated universes; he appeared earlier in 'The Simpsons'' latest season finale, "Dangers on a Train." Furthermore, MacFarlane's upcoming role will mark his first speaking stint on 'Futurama,' having previously contributed a singing part for the animated feature 'Into the Wild Green Yonder.'

In addition to MacFarlane and Silverman, the final 13 episodes of 'Futurama' feature guest stints from the likes of 'Game of Thrones' star Emilia Clarke, basketball legend Larry Bird, 'Star Trek''s George Takei, original Batman and Robin Adam West and Burt Ward, as well as Homer Simpson himself, Dan Castellaneta.

What say you? Are you sad to see 'Futurama''s (likely) final episodes kick off tonight? What do you think of Seth MacFarlane giving voice to Seymour? Watch the latest trailer below, and give us your thoughts in the comments!