So many movies have been turned into musicals that shouldn’t have been. (See: “Pretty Woman,” “Carrie” and “Ghost.” Better yet, don’t.)

But a precious few get the transition juuuuuuust right. One of those that did: “Monty Python’s Spamalot.” The show’s subtitle of “A musical lovingly ripped off from the motion picture ‘Monty Python and the Holy Grail’” is the first hint that the original’s spirit remains firmly intact.

“Spamalot” is gloriously silly, as the national tour that came through the Garde Arts Center on Saturday proved with great enthusiasm.

Of course, “Spamalot’s” success can be traced in part to the fact that Python original member Eric Idle was the driving force behind the adaptation. Idle handled the book and lyrics and collaborated with John Du Prez on the music. The result? A cart full o’ Tony nominations after the show’s 2005 Broadway debut and three wins, including the Tony for Best Musical.

The original movie, meanwhile, was released 43 years ago, but its irreverence certainly holds up.

Watching “Spamalot” on Saturday, I realized that one of its many strengths is that it doesn’t worry about developing a significant storyline. Sure, King Arthur is leading a quest to find the Holy Grail, but it’s really the absurdist comedy that counts. Consequently, the show is a celebration of song, dance, and comedy — no need to worry about tying up pesky plot points or making things track logically. It’s sketch comedy with a big, boisterous Broadway score.

The cast on this tour was swell, funny in a way that pays homage to how the Python gang played the roles in the original while still giving it their own unique spin. Their voices were robust, and, just as important, they had good diction, so we could hear every witty line.

Arguably the powerhouse vocal performance of the night was Philip Huffman as Sir Galahad and Leslie Jackson as The Lady of the Lake sounding glorious when duetting on “The Song That Goes Like This.”

All along the line, Jackson made the most of her numbers, including “The Diva’s Lament,” when The Lady of the Lake returns during Act II to complain that her character has been offstage way too long.

Meanwhile, the multitasker of the night was Adam Grabau, who played Sir Lancelot, The French Taunter, Knight of Ni, and Tim the Enchanter, all to crowd-pleasing effect.

The dance numbers were amusing, with Not Dead Fred (played by Tim Hackney) doing a loose-limbed soft-shoe to the song “I Am Not Dead Yet” and knights swinging yellow umbrellas and Gene Kelly-ing their way through “Always Look on the Bright Side of Life.” (That latter song was pulled from the Monty Python film “Life of Brian.”)

Idle populated “Spamalot” with plenty of throwaway lines and quick-hit tomfoolery. When King Arthur explained that the grail is a cup, but it’s really a symbol, a musician in the pit hit a cymbal. French stereotypes (hello, mime!) came pouring out from the French castle and then, naturally, did a cancan. In one sequence, the Lady of the Lake was joined by her “Laker Girls” for a cheerleader-esqeue dance routine.

It’s true that comedy often works best with the element of surprise. “Spamalot” scored in spite of that. Fans at the Garde applauded what they knew were the signs of a classic bit coming up — King Arthur trotting onto the stage, with sidekick Patsy making horse-hoof noises with coconuts; the French Taunter popping up from a castle roof. But that didn’t dim anyone’s enjoyment. The riotous laughs throughout the night were proof positive of that.