★★☆☆☆

Confusing. Haphazard. Far-Fetched. Convoluted.

For centuries, such words have been used repeatedly to describe Cymbeline, Shakespeare’s rarely staged late tragicomedy that is being performed on the Boston Common by Commonwealth Shakespeare Company through Aug 4. George Bernard Shaw even famously called it “stagy trash.”

Trash, I’m not sure, but it is hardly among Shakespeare’s best. It does seem—as Madonna would say—reductive, borrowing an awful lot from things like Romeo and Juliet, Othello, King Lear, and As You Like It. It’s hard enough to care about the sprawling and unusual patchwork as it is, but matters are not helped by Fred Sullivan Jr.’s rambunctious and focusless production that succeeded only in exhausting this critic rather than entertaining him.

Cymbeline (the accomplished Tony Estrella) is the widowed king of Britain who has remarried an evil queen (the not cruel enough Jeanine Kane). The queen wants Cymbeline’s only daughter, Imogen (Nora Eschenheimer), to marry her son, Cloten (Kelby T. Akin). But Imogen isn’t interested in Cloten and instead has already married Cymbeline’s ward, the penniless Posthumus Leonatus (Daniel Duque-Estrada). The king is furious when he discovers this and quickly banishes Posthumus to Italy. Meanwhile, the queen plots with her henchman, Doctor Cornelius (a deliciously snide Mihir Kumar) to poison Posthumus so that Imogen will be free to marry Cloten (Cloten, for the record, is being performed like an Edwardian version of Stifler from American Pie).

And here’s where things begin to make no sense: Posthumus arrives in Italy and begins bragging about how faithful his wife is. The meddlesome troublemaker Iachimo (a committed but exhausting Jesse Hinson) overhears this and bets Posthumus that he can make Imogen unfaithful, and so he travels back to Cymbeline’s kingdom to seduce her. He fails but steals her bracelet and falsely presents this to Posthumus as proof that he has slept with her. Taking him at his word, Posthumus instructs his servant, Pisanio (the always great Remo Airaldi) to kill Imogen. As you do.

And all of this doesn’t even take us up to intermission. Add in an invading Roman army; Imogen running away, dressing up as a boy, and hiding away in a cave with an old man; an attempted suicide; an actual suicide; a decapitation; a war; an appearance by Jupiter; and a denouement that lasts almost until sunup and you’ve got Cymbeline in a nutshell.

Fred Sullivan Jr.’s production aims to really play up the mythic aspects of the play and yet it is infused with zero whimsy, adventure, or imagination, even a smattering of which could have made Cymbeline the ideal summertime treat for theatergoers young and old. It has the antics of an animated film—and the broad performances to go along with it—but the clowning around gets old and bogs down the pacing over the overlong play like a wet diaper. (For my own sanity, I’m not even going to go into the decapitation scene or how the battle is reimagined as a game of dodgeball.) Most curiously of all, the production seems to be stuck in several different time periods, none of them particularly mythical or whimsical.

Some of these problems are only aggravated by the puzzling design elements (said to have been inspired by both Disney animated films and Edward Gorey illustrations) that cloud rather than clarify. Hill and Patrick Lynch’s unit set looks like a diorama with mismatched rooms that is half sunken into the ground, and it is frequently awash in harsh lighting (by Eric Southern) that would be more at home in a crumbling boardwalk funhouse. Also problematic are Elisabetta Polito’s costumes, which are lovely enough half of the time but look just plain cheap the rest of the time (I even spotted some denim—I rest my case).

While it is true that Nora Eschenheimer is giving a commanding performance as our heroine Imogen, the intensity and spunk of her performance do not transform the play into any more of an entertainment. She plays the role kind of like a Disney princess, which means on one hand that she nails the feistiness and free spirit of the role, but it also means that, on a scale from one to 10, she acts at about an 11 the entire evening with the kind of “gee whiz” inflection usually immured to productions of Annie or Bye Bye Birdie.

Maybe George Bernard Shaw was onto something, after all.

CYMBELINE. THROUGH 8.4 AT PARKMAN BANDSTAND ON THE BOSTON COMMON. COMMSHAKES.ORG