The secret of the Star's success is twofold: The company knows what its audience wants -family entertainment with a lot of laughs - which is what it dependably delivers; and it has carved out a niche in musical parodies that send up popular movies or shows, ranging from "Star Trek" to "Les Miz" to "My Big Fat Greek Wedding." When audiences hear the title, they know what to expect.

The cabaret theater's Christmas show is "Christmas Vacation: The Bi-Polar Express," which is funny and energetically performed by a talented and personable cast. But "Christmas Vacation" is not one of the Desert Star's most clever or entertaining productions.

First, in this case, the title is a red herring because writer/director Scott Holman never follows up on the bipolar idea. In fact, the show never establishes anything definite to parody. Since the characters are members of the Bailey family, and the main couple are named George and Mary, we expect a takeoff on Frank Capra's perennial holiday favorite, "It's a Wonderful Life," but this never materializes, either.

Without an established structure, "Christmas Vacation" is like a ship without a rudder, occasionally coming up with a good joke or musical number but mostly just wandering. The story is simple: George has to spend Christmas with his extended family, whom he dislikes intensely, to satisfy the terms of his father's will. His conniving sister Virginia and her browbeaten son Horace concoct a plot to steal the inheritance.

Most of the humor comes at the expense of Larry Miller, including the show's best line: When someone asks if Miller will purchase all the trees at the Festival of Trees, Uncle Roy snaps, "Why not? He buys every other 7-foot piece of crap." The funniest character is a ditsy marriage counselor named Mariah, played with nearsighted bewilderment by Kerstin Davis, who is so busy spouting New Age pseudophilosophy that she can barely navigate the real world.

The cast has great fun with the show as well as spontaneously interacting with the audience. "Christmas Vacation" is an ensemble effort with contributions from all: Bob Longoria's long-suffering George; Lisa Grow's stylish Virginia; Brian Bahr's empty-headed Horace; Jack Drayton's smart-mouthed Uncle Roy; Brooklynn Pulver's sweet-tempered but sassy Aunt Ladine; and Heather Ferguson-Elmer's peacemaker Mary.

But probably the most fun is watching Aaron Swenson, fresh from his starring gig in "Hedwig and the Angry Inch," play five roles, ranging from a living TV video to a motor-mouthed auctioneer.

Christmas Vacation

Where: The Desert Star, 4861 S. State St., Murray

When: Tuesday; continues twice nightly except Sunday through Jan. 7, with extra matinee performances on Saturdays; call 801-266-2600 for schedule.

Running time: 1 hour, 20 minutes

Tickets: $13 for evening shows, $11 for matinees, with discounts for students, seniors, and children. Call 801-266-2600 or visit http://www.desertstar.biz.

Bottom line: "The Phantom of the Opera" it isn't, but if you're looking for lighthearted holiday entertainment, "Christmas Vacation" is family fun.