For a certain generation that came of age watching trippy, bell-bottomed Saturday-morning TV shows while sucking down bottomless bowls of Count Chocula, the words are as sacred as, "Here's the story of a man named Brady" or "Scooby-Dooby-Doo, where are you?" For [movieperson id="190407"]Will Ferrell[/movieperson], they're the inspiration for this never-before-seen clip from his June blockbuster [movie id="369697"]"Land of the Lost."[/movie]

"Marshall, Will and Holly/ On a routine expedition," Ferrell sings as park ranger Rick Marshall, performing his ditty for, well, Will (Danny McBride) and Holly ([movieperson id="201154"]Anna Friel[/movieperson]). "Met the greatest earthquake ever known/ High on the rapids, it struck their tiny raft/ And plunged them down a thousand feet below/ To the Land of the Lost."

Also along for the ride is [article id="1601144"]Lonely Island member Jorma Taccone[/article], unrecognizable as friendly cave-boy Chaka -- as well as a ukulele and one particularly scary-looking mosquito.

Ferrell and his "LOTL" pals sent over the exclusive clip to help MTV celebrate the taping of the latest [article id="1605378"]"Spoilers" show[/article]. Alongside new footage from "Star Trek" and the "Harry Potter" and "Transformers" sequels -- as well as Zack Snyder's "Watchmen" in its entirety -- the "Land of the Lost" footage was unveiled to our geek-heavy, approving audience.

Will's clip was met with a lot of laughter from our crowd of 300, particularly because it hits the right note of mixing self-reference with humor for those who might be unfamiliar with the movie's source material: a blissfully cheesy classic from Sid and Marty Krofft that ran from 1974-1976. In case you haven't seen the show's classic opening, you can check out the original theme here.

The joke of the scene is that Ferrell's Ranger Rick is "spontaneously" writing the song, apparently to make up for some sort of argument he had with the others. As he hits the part of the original intro where the TV show's characters fall down the rapids and scream, a freaky mosquito begins sucking blood out of his neck, leading the others to shriek on cue. "That's good!" he says approvingly.

And just before he passes out, Rick attempts to hit the song's chorus, explaining: "Here's how I end it: a little arpeggio, nothing fancy."

Directed by "Lemony Snicket" filmmaker Brad Silberling and boasting special effects as funny as they are menacing, Ferrell's "Land of the Lost" might not be fancy, but it promises to be an expedition far from routine.

Check out everything we've got on "Land of the Lost."

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