Apart from a few burning cast questions, The Simpsons has plenty lined up for Season 27 this fall, including a premiere plot with Girls star Lena Dunham that sees Homer and Marge hitting a new low in their marriage. Now, EP Al Jean explains the cause of their separation, as well as a role for SNL favorite Kate McKinnon, and an episode devoted to Bart’s Boyhood.

Speaking with Variety, executive producer Al Jean addressed a broad span of topics (save any progress on negotiations with Harry Shearer), also explaining that Homer’s narcolepsy plays a factor in the upcoming split between he and Marge. Apart from the cast of Girls, the new season will also feature a beloved Simpsons Movie character’s return, as well as Sideshow Bob’s long-awaited victory:

In the premiere, it’s discovered after all the years Homer has narcolepsy and it’s an incredible strain on the marriage. Homer and Marge legally separate, and Homer falls in love with his pharmacist, who’s voiced by Lena Dunham. We’ll have cameos from the other women from “Girls.”

We have an episode coming up where Lisa befriends a homeless woman who turns out to be an incredible singer. The woman’s voiced by Kate McKinnon, but the singing is done by Natalie Maines. In another episode, Spider Pig makes his return. Sideshow Bob appears in a segment, and we finally see him do something he’s wanted to do for 25 years.

And we have an episode based on the film “Boyhood.” It’s a flashback/flashforward about Bart. We go to various points in his life and his life to come which I think came out really well.

Jean also spoke to the unlikelihood of another movie while the show remains in production, as well as the legacy of the late Sam Simon, but does Season 27 seem off to a strong start? Homer and Marge will surely patch things up before the premiere’s end, but is shaking up the status quo a fresh start, or a gimmick at this point?

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