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When two legendary behemoths get in each other's space — say, King Kong and Godzilla — results can be tragic. But when the LEGO Group and The Simpsons come together, it's a little slice of Springfield heaven. A very pricey slice.

In an editing bay on the Fox Studios lot in Los Angeles, final touches are being put on a special LEGO-themed Simpsons episode (airing Sunday, May 4) that is the most ambitious and expensive half-hour in the program's 25-year history. Cheekily titled "Brick Like Me" and set almost entirely in a LEGO world, it's also episode No. 550, a staggering accomplishment for a primetime series. This has left the well-seasoned
wisenheimers on the production team feeling an odd combination of over-the-moon excitement and enough-already boredom.

"We've literally been at this thing for two years — twice the time it takes to do one of our regular episodes — and that's way too long for comedy people to live with the same jokes," says Matt Selman, the executive producer in charge of the episode. "It's been an epic process. First, we had to convince [executive producer] Jim Brooks and our showrunner, Al Jean, that a LEGO episode was a great idea and not just an excuse for our staff of nerds who grew up in the '70s to crack LEGO jokes. There needed to be a real emotional story there."

Then that story — in which Homer must choose between living in an idyllic LEGO universe or the real world — had to meet with the approval of the LEGO folks. "We're pretty picky about how our brand is represented, and The Simpsons, which is so famous for its satire, has its own distinct point of view," says Jill Wilfert, the LEGO Group's vice president of licensing and entertainment. "No one at the show is used to dealing with creative input from the outside, so there was certainly some back-and-forth to get it all right. But, at its core, the LEGO brand is all about creativity and imagination. We respect that in others."

That's no corporate bull. Though "Brick Like Me" is definitely tamer than most other Simpsons episodes, Wilfert did approve a sequence where LEGO Marge and LEGO Homer get frisky and are clearly heading to the bedroom. Their afterglow scene, with LEGO arms, hands and feet pulled apart and scattered everywhere, is priceless. "This was a chance for us to be a little edgier than we might normally be," Wilfert says. "And because we'll likely bring younger viewers to The Simpsons, it was an opportunity for them to be more family-friendly."

This marriage actually began several years ago, when the 82-year-old Danish toy company approached Fox about marketing a construction set of the Simpsons' home, including minifigures of Homer, Marge, Bart, Lisa, Maggie and neighbor Ned Flanders, which went on sale in February. While that merchandising was still in the works, Wilfert pitched another idea: "We went to the guys at The Simpsons and said, 'Wouldn't it be fun if you did your opening couch sequence LEGO-style?' They quickly came back to us and said, 'Forget the couch; let's do an entire episode!'"

Selman and longtime staff writer Brian Kelley devised a storyline that kicks off in a blissful
LEGO version of Springfield where, notes Marge, "everything fits with everything else, and nobody ever gets hurt." This world seems perfectly normal to the characters — until, that is, LEGO Homer starts having flashes of an alternate-universe life in which he's the good ol' Homer we know and love. "He begins to realize this LEGO world he's living in is not where he and his family really belong," says Kelley. "He has to figure out why they are there and what it all means."

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