There’s an inspired silliness to “Austenland,” an erratic, entertaining comedy with an inspired premise. It imagines a Disneyland for women besotted with Regency romance in all its bodice-tingling glory. The English resort promises its guests a unique Jane Austen vacation experience, dressing them as damsels and staging dinners, croquet afternoons and grand balls where the guests mingle with the resident theater troupe. Each tourist gets her own shot at make-believe romance. And as we know from fantasy theme parks like “Jurassic Park” and “Westworld,” absolutely nothing can go wrong … go wrong … gowronggg …

Thirtyish New Yorker Jane Hayes (Keri Russell) fell in love with “Pride and Prejudice” as a preteen, and utterly lost her mind when she saw the BBC miniseries starring Colin Firth as hot, taciturn Mr. Fitzwilliam Darcy.

Now she’s living in a fantasy world. Her bedroom is a frilled, ruffled nightmare of Anglophilia that would dismay Laura Ashley. Her living room features a life-sized cardboard cutout of Firth in breeches and tailcoat.

Since “all the good men are fictional,” Jane spends her life savings on an Austenland fling, arriving at Heathrow Airport in a period dress that makes her look like Raggedy Ann’s dowdy cousin. She encounters wealthy fellow tourist Elizabeth (Jennifer Coolidge), a goodhearted ignoramus, and the pair visit their world of faux-mance together.

Daily life at the resort drifts in and out of rationality in a way that tickled me. Director/co-writer Jerusha Hess (who co-wrote “Napoleon Dynamite”) has a fine eye for absurd detail. Austenland’s operator (Jane Seymour) cuddles an inert, stuffed lamb; her telephone is covered with a needlework tea cozy. The traditional country house breakfast includes bagels.

The comedic goods are not parceled out evenly. Russell has only one joke as Jane, who tries to go with the program but finds her 21st-century self breaking out inappropriately. Coolidge, a veteran of Christopher Guest’s improv gems, is uproarious as a scatterbrain who can’t do needlework without stitching her lace glove onto the fabric. She is over the top in a way rarely seen outside Looney Tunes.

But “Austenland’s” real revelation is Georgia King. King is gorgeous — picture an Amazonian Reese Witherspoon — and a world-class goof. As Jane’s fellow guest and nemesis, King elevates curveball line readings to an art form. She tackles her role with a daffy fearlessness that recalls Johnny Depp’s Capt. Jack Sparrow. There’s not been a romantic rival, or a human being, quite like this onscreen before. King and Coolidge elbow Russell out of her own movie.

While I enjoyed “Austenland,” it never jells. It’s like a genial amateur theatrical where you groan and laugh along with the cast members, who know the plot is creaky and the jokes are broad. Its self-satirizing comic-strip oddness keeps it from being boring.