It’s become an annual tradition for “The Simpsons” to celebrate Halloween with a horror-filled episode of “Treehouse of Horror”, which puts a genre spin on the classic animated comedy. In anticipation of this year’s episode, executive producer Al Jean tells EW that next year’s episode will be landmark decades in the making.

“Next year, ‘Treehouse of Horror XXX‘ will coincidentally be Simpsons episode 666,” Jean reveals before joking: “As we planned it in 1989!”

Airing Sunday at 8 p.m. ET/PT on Fox, this year’s Halloween installment, “Treehouse of Horror XXIX,” will wink at Jurassic Park, Invasion of the Body Snatchers, and The Three Faces of Eve. And in the opening of the episode, “Cthulhu, the ancient creature of the sea, gets into an eating contest with Homer,” Jean recently told EW. “I’ll leave you to guess who might win.”