The Simpsons and Family Guy, cartoons that both air on Fox, will have a crossover episode that will air later this month.

'Simpsons' & 'Family Guy' Crossover

Family Guy producer Richard Appel, who previously wrote for The Simpsons, got the go-ahead from The Simpsons producers to create an episode of Seth MacFarlane's hit animated series in the world of the 25-year-veteran. The episode, which will feature the cast of characters from both series in Springfield, came together rather seamlessly once the Simpsons producers realized what Appel was trying to do.

“From the start, Al [Jean] and Jim [James L. Brooks] and Matt [Groening] were on board with it being an episode of Family Guy… with the condition ‘Do us proud, please don’t kill Marge, and let us read the script,” Appel told Entertainment Weekly. “But there was a welcomed level of trust on both sides that they weren’t going to rip the script to shreds and we weren’t going to rip Springfield to shreds…. We said to Jim and Al and Matt : ‘It’s not our idea to do something that you’d be watching for the first time when it airs and say: What have we done? We want it to be something you’ll also like.'”

In the crossover special, the Griffins will head to Springfield, where the hapless patriarchs hit it off right away, but eventually develop animosity towards one another over beer. Meanwhile, Bart and Stewie will bond over their love of pranks, though Stewie's are admittedly a bit more sinister. Lisa will help Meg achieve a greater level of self-confidence, while mothers Marge and Louis hang out. Santa's Little Helper, Brian and Chris will be worked into the plot as well. Lesser characters from the series also made the cut.

“You can’t get around the fact that both worlds have an anchorman and both worlds have a sea captain,” noted Appel, who also revealed that Bob Belcher (H. John Benjamin) will have a cameo.

“After the table read, I did say to Seth, ‘We’re six minutes long,'” Appel laughed. “And he said, ‘Um, I would not worry about the length. Fox will be happy making this an hour long.”

The hourlong The Simpsons/Family Guy crossover will air on Fox Sept. 28 at 9/8c.