After weeks of hype and yet more hype, “Monty Python’s Spamalot” proves to be partially worthy of the buildup. In some respects, the show is far better than it has any right to be; just as often, it’s a strained effort that leaves little, if any, impression. Eric Idle’s stage adaptation—like the original 1975 movie, “Monty Python and the Holy Grail”—tumbles forth in a pileup of sketches that never quiet coalesce into something more. Maybe that’s okay. Maybe not. What you get is a big honking Broadway spectacle that tries very hard to convince you it’s perfectly right-and-good to pay steep prices for what is basically a super-elaborate Second City revue. At the core of the story’s rough outline are Britain’s King Arthur (Tim Curry, a steadying, mirthful presence), his Knights of the Round Table (Hank Azaria as Sir Lancelot; David Hyde Pierce as Sir Robin; a very funny Christopher Sieber as a preening Sir Galahad in a Michael Bolton wig) and their search for the grail. Many of the film’s bits are dutifully recreated, presumably because it might seem conspicuous if, say, King Arthur’s battle with the Black Knight were missing. (For the record, that scene here feels expendable.) The “Forbidden Broadway”-style gags are also a worn-out and frankly stupid addition. “Spamalot” blooms into something genuinely entertaining when it abandons all that nonsense and pushes the Pythonisms to their furthest possible conclusion. That dead cow the taunting French hurl over the battlements? She gets her own song, aptly titled “The Cow Song,” in which all manner of French clichés are mercilessly skewered with an Edith Piaf vibrato. The Lady of the Lake (a mama of a performance from big-voiced Sara Ramirez, with her transgendered, Alexandra Billings quality) is realized in flesh-and-blood with her own Vegas-on-steroids lounge act. What’s missing from the show is a sense of slightly out-of-control precariousness. Mike Nichols’ slick direction goes down easy, like candy—and ultimately feels just as disposable. (Nina Metz)

Monty Python’s Spamalot is playing at the Shubert, 22 W. Monroe, (312)902-1400, in a sold-out pre-Broadway run through January 23.