Arizona Theatre Company's production of Oklahoma! isn't religious about the tenets and philosophy of the original 1943 production.

Joey McKneely's new choreography obliterates the groundbreaking work of Agnes de Mille, and Vivian Matalon has changed the directions used by Rouben Mamoulian.

But theater is defined by change, and those who criticize ATC's new take on Oklahoma! are missing the point.

This lavish remounting of one of this century's most important musical theater creations is everything theater should be -- and often no longer is. Believable performances intertwine with exciting dancing, pure singing voices and an interesting story to create a realistic piece of Americana.

The Oklahoma territory is populated by cattlemen and farmers in general, and lovers Curly and Laurey specifically. Most of the action of the play takes place in one day, starting the morning of the traditional "box social" to raise money for the school.

Feisty Laurey (Becky Watson) wants to go to the event with Curly (Jeff Stafford) but doesn't want him to know it. Attempting to make Curly jealous, she agrees to go with enigmatic farmhand Jud (Michael Gruber).

Confusion mounts as Curly and Jud jockey for position in the heart of the woman they both want.

Oklahoma! is important for many reasons, but mostly because it is the first musical to integrate song and dance (notably ballet) into the unveiling of the plot.

It was the first pairing of Richard Rodgers and Oscar Hammerstein II, and paved the way for blockbusters such as South Pacific and The King and I. And all its songs are winners, unlike most modern musicals whose songs are usually pedestrian cliches. Classics like "Many a New Day," and "I Cain't Say No" demonstrate a songwriting skill that is almost extinct.

This musical is also important for what it lacks: crashing chandeliers and onstage helicopters. It avoids the need for flashy gimmicks by possessing a story with depth, reason and purpose.

These elements old and new are combined in a breezy staging that captures the tradition of Oklahoma! yet gives it a contemporary sheen. Notable are the costumes designed by David Loveless, R. Michael Miller's clever set designs, and the good use of lighting by Richard Nelson.

Enjoyable performances are turned in by the 22-person cast, especially Stafford, Watson, Kelli Maguire as man-crazy Ado Annie, and Marsha Bagwell as Aunt Eller. Also notable are Susan Misner and Elliot Jordan, the principles in the dream ballet.

Musical accompaniment is ably provided by two dozen members of the Phoenix Symphony, under the direction of Jack Lee.