According to my Playbill, the Shubert Theater is currently home to Bin Faaarkrekkion’s new Moosical, “Dik Od Triaanenen Fol (Finns Ain’t What They Used to Be).” The story of Finland’s transition from an agricultural society to an industrial one, which features the talents of the East Finland Moose Ballet, is highlighted by such songs as “I Hear Your Nokia But I Can’t Come In” and “Foek You, Farmers.” The action takes place entirely in a sauna.

Before a line of dialogue has been spoken – before even the overture, which will be interrupted momentarily by the shooting of a member of the brass section – “Monty Python’s Spamalot” ushers us into very silly terrain. The fake Playbill is only the beginning. Beneath the show’s puffy cartoon clouds, expect flying cows, murderous can-can dancers, the Laker Girls, and flatulence – in short, a major dose of Python lunacy.

“Spamalot,” according to a somewhat more reliable page of my Playbill, has been “lovingly ripped off” from the motion picture ‘Monty Python and the Holy Grail.'” Scenes and characters familiar from that 1975 classic are here: See King Arthur being followed everywhere by his trusty servant Patsy, who bangs coconuts together to simulate a horse. Witness the taunting Frenchmen (“I fart in your general direction!”) and the Killer Rabbit. Gaze upon that sorrowful damsel in distress, Prince Herbert. The show doesn’t borrow general ideas from the film: Whole chunks of the screenplay have been reproduced here, lines that, if you happened to encounter them at an impressionable age, will now come flooding back verbatim.

Clearly I’m not the only one for whom this is true. There’s a whoop when the lights go out, a roar when King Arthur and Patsy first appear, and noisy applause at the close of many cherished bits. “There are some who call me … ” began a character, and people all around me supplied his name,” Tim. “This is wonderful: Part of the evening’s fun is being in a room with all those overeager devotees. Well, us overeager devotees.

Eric Idle has taken the screenplay he wrote with his fellow Pythons (Graham Chapman, John Cleese, Terry Gilliam, Terry Jones, and Michael Palin) and fashioned it into a Big Broadway Musical. He has written the book and lyrics (and, with John Du Prez, the music) of this goofy old-and-new spectacle. King Arthur (Tim Curry) still goes in search of the Holy Grail with his knights Sir Lancelot (Hank Azaria), Sir Robin (David Hyde Pierce), Sir Galahad (Christopher Sieber), and more. They still encounter the Knights Who Say “Ni,” among other ridiculous perils. But in this version of the story, their ultimate quest is – wait for it – to reach Broadway.

Mr. Idle’s major innovation is to make “Spamalot” a Broadway musical about Broadway musicals. He expands some songs from the film (like “Brave Sir Robin,” an ode to noble cowardice) and creates others from scratch. “Fiddler on the Roof” and “West Side Story” are mocked. The Lady in the Lake (Sara Ramirez) complains about not having enough to do, and threatens to call her agent. She and Sir Galahad sing “The Song that Goes Like This,” a send-up of Broadway cliches. He begins,

Once in every show
There comes a song like this
It starts off soft and low
And ends up with a kiss

After a brief disagreement about which key to sing in, the Lady answers Galahad: “I’ll sing it in your face / While we both embrace.”

I don’t envy this cast. With the exception of Ms. Ramirez, they are following in cherished footsteps. Mr. Azaria draws the toughest assignment, playing a couple of roles created by the incomparable Mr. Cleese. Being an exceptionally funny man, Mr. Azaria holds his own, but no one’s memories of Mr. Cleese are likely to dim. (Particularly since he supplies the voice of God here.)

As King Arthur, Graham Chapman anchored the film with a mix of exasperation and hauteur. “But I am your king,” he fumed to the political-science-spouting peasants. Mr. Curry takes a different approach. He adopts a tone of reasonableness and almost feline passivity – still funny, but subdued. The restraint may be a symptom of Mike Nichols’s effort to keep the show from flying apart in five or six directions. The director deserves credit for imposing discipline, though in Mr. Curry’s case more madcap might have helped.

In their supporting roles, the fleet-footed Michael McGrath and the inexhaustible Christian Borle stand out. But it’s Mr. Pierce who steals the show. He cracks jokes, he sings, he dances – he even takes an impressive turn at the piano. The song in which he explains what it really takes to succeed on Broadway is a highlight of the evening. I won’t ruin the joke for you, but suffice it to say that one of Mr. Idle’s sharper lyrics runs: “If it’s not kosher, then no show, sir.”

Maybe the most wonderful thing about encountering Monty Python was the shock of the bizarrely new. Your sense of the universe expanded – it had to expand – to accommodate such absurdities as a Holy Hand Grenade and a Trojan bunny. Mr. Idle’s musical version doesn’t match the transgressive thrill of the original. A show that relies so much on rote recreations of a familiar screenplay couldn’t.

The real trouble is that much of Mr. Idle’s new material feels familiar, too. Making fun of Broadway cliches has become, itself, a Broadway cliche. Mr. Pierce’s big number aside, there isn’t much in this vein that hasn’t been done better by “The Producers” or “Urinetown.” It won’t do to get all cerebral about a show that includes lines like, “Your mother was a hamster and your father smelt of elderberries.” Still, “Spamalot” adds to the charge that the Broadway musical has lost a point of view about everything but itself.

At moments, the show has a very un-Python tendency to knuckle under to the traditions it claims to mock. “The Song That Sounds Like This” gets a suspiciously sincere reprise in the second act. Likewise, “Find Your Grail” is an uplifting song not so different from corny anthems in other, lesser musicals. Make no mistake, there are laughs galore in this show – more than just about anywhere else in town. Still, judged against the Python record of original, subversive, unrelenting comic wizardry, “Spamalot” can sometimes disappoint.

But on the strength of its best moments, if Mr. Idle or another of his fellow Pythons – or better yet, several of his fellow Pythons – decided to treat Broadway to a genuine all-new musical, I’d be delighted. Almost any sort of musical would do, as long as its creators found a subject about which they could be crude, weird, utterly new, and merciless – in short, one that would allow them to be Monty Python. Finland, anyone?

(225 W. 44th Street, 212-239-6200)