A little more than halfway through the extremely silly “Gail Daughtry and the Celebrity Sex Pass,” the main character questions the very idea behind her journey, and, by extension, the movie itself. In it, Zoey Deutch’s character Gail embarks on a “Wizard of Oz”-like journey from Kansas to Hollywood to even the score with her fiance and have sex with her celebrity free-pass: Jon Hamm.“Ridiculous. It’s stupid. Just an utterly pointless premise,” she says, defeated after yet another setback. “It’s like, why?” John Slattery — playing John Slattery, or at least a sadder and more comedic version of John Slattery who hasn’t worked in a decade, who has taken up self-defense as a hobby and whose text messages to his former “Mad Men” co-star go mostly unanswered — tells Deutch’s Gail that they’re too far into this thing to give up now. Indeed. This is very much the spirit of this unabashedly absurd film from director David Wain, who, with his cowriter Ken Marino concluded early on that the idea was really stupid, didn’t make sense and went nowhere. For those reasons, they said, they had to make the film.In the same way Wain’s “Wet Hot American Summer” was both love letter to and send-up of the weirdness of summer camp, “Gail Daughtry” takes on Hollywood and celebrity in a heightened and anarchic reality. Wide-eyed, never-left-Kansas Gail hasn’t even heard of the concept of the celebrity free pass at the start of the movie. Neither has her daffy high school sweetheart, but a few hours later, she’s shocked to find out he’s already found an occasion to use his. And thus begins her quest to find, and bang, the man who played Don Draper.