''Napoleon Dynamite,'' the new cult comedy about an Idaho nerd, borrows its title character's name from a nom de plume used by Elvis Costello in the credits of his 1986 classic, ''Blood & Chocolate.'' Or does it? ''I listen to hip-hop, dude,'' swears writer-director Jared Hess, 24. ''It's a pretty embarrassing coincidence.''
Hess is a Mormon, and while Costello buffs were poring over their Rhino reissues a few years ago, the budding filmmaker was doing missionary work in a Chicago suburb when an odd man on the street beckoned him over. ''He made a comment about our names, because when you're a missionary, you're called Elder and then your last name. I was like, 'So, what's your name, sir?' He was like, 'Napoleon Dynamite.' I was like, Oh my gosh, that is the freshest name I've ever heard -- this has to be the title of the movie I'm gonna do!'' Cut to summer 2003; two days before the end of shooting, a high-school-age extra asks, ''This is based on the Elvis Costello alias, right?'' ''I went, Whaaat? Had I known that name was used by anybody else prior to shooting the whole film, it definitely would have been changed.'' So basically, Hess got punk'd by a Costello fanatic? ''I don't know, dude. This was an old, old Italian man -- 70-some years old.''
Costello's camp declined to comment on the Fortean fluke. But since neither the Lou Costello nor the Elvis Presley estate has sued him, maybe he'll cut the kid a break.