David Turner in Buyer & Cellar at Old Globe Theatre.

Alex Moore, struggling actor, not only works at Disneyland, he’s the “Mayor of Toontown.” He hates it so much he calls the “happiest place” on earth “Mousechwitz.” The drive from his Los Feliz studio apartment, in a bunged-up VW Jetta, takes forever, and he can’t fake his displeasure for patrons. Except for his growing relationship with Barry, Alex’s life is the opposite of the utopia his distant relative, Sir Thomas More, wrote about.

But other than performing onstage with the iconic Barbra Streisand, what would Alex’s utopia look like? Jonathan Tolins’s solo show Buyer & Cellar inverts the question: what would working for Barbra Streisand — in her utopia — feel like?

Throughout her career, fans and publishers urged Streisand to write her autobiography: the death of her father when she was 18 months old; how she challenged America’s concept of beauty; how she has won every conceivable award as a performer: Oscar, Tony, Emmy, Golden Globe, Kennedy Center acclaim; and how she rose from impoverished childhood in a dinky Brooklyn apartment to her Monte Carlo–like, $100,000,000 estate at Point Dume in Malibu. The Ugly Duckling does the American Dream.

Instead of an autobiography, Streisand wrote My Passion for Design, about her “dream refuge” overlooking the Pacific. She weaves her life story through the narrative. The coffee table book — signed copies begin at $600 — reflects Streisand’s “passion for furniture,” and color and texture and obsession for detail, in great detail.

One of the estate’s four structures is the Barn. The almost 6000-square-foot building has a basement out of Elmer Rice: it’s a street scene with stores — the names often ending with an extra e (as in “the Gift Shoppe”) — where many of Streisand’s prized possessions are for sale. Or for barter, since they don’t have price tags.

Alex Moore gets the job as the basement’s “customer service” rep. He mostly dusts while the frozen yogurt machine hums in the Sweet Shoppe. Then the Icon enters without fanfare. She’s playing a role: Sadie the Shopper (aka, the buyer in the cellar). Alex instinctively becomes the Shopkeeper. They haggle about the cost of a doll named Fifi. Alex, out of the blue, asks $850. Streisand says $500. What must Alex do? How should you behave in someone else’s utopia? He has the effrontery to hold his ground.

We don’t see the doll and can’t gauge its worth (as described, the real Fifi may cost five figures). Erik Flatmo’s minimalist set has few furnishings and no small objects. And we don’t see Barbra either, since actor David Turner plays Alex, Streisand, Barry, and the other characters in this solo performance.

We hear, much more than see, and imagine the basement-boutiques “just like any other mall, except for the total lack of customers or employees” and everything “displayed with totalitarian precision.” Tolins’s writing is laced with vivid descriptions. After a while, thanks to Philip S. Rosenberg’s lighting, which demarcates playing spaces, and Lindsay Jones’s sounds and original music, we know our way around the basement: the yogurt machine’s over in the Sweet Shoppe, Bee’s Doll Shop’s across the way, and the Gift Shoppe, which includes wrapping paper and ribbons, right here.

Turner performs the dialogue with turns of the head: now Barbra, becoming testy and showing the Diva’s dark side; now Alex improvising like mad and trying not to drop character, throw up his hands, and shout: “This is BIZARRE!”

Alex’s lover Barry gets the robust reactions. Barry’s a one-note character: the Ventilator. As he becomes jealous of Alex’s budding relationship with Streisand, Barry cuts loose with one nasty zinger after another, including “this incredibly privileged, powerful woman still acts like a Dickensian victim.”

Throughout David Turner shifts from wisdom to innocence: wise when he recalls events, gaga-eyed innocent when experiencing them, as a dyed-in-the-wool ”Barbra Queen,” for the first time. He is always engaging and at his best when he creates a palpable intimacy between Barbra and Alex, by himself.

Turner gives a tour de force performance. At times, however, the playwright lets him down, because Tolins wants to give one too. It’s rumored that Streisand yearns to play Mama Rose in Gypsy (go for it, Babs!). Turner does several versions. Though funny — and this show often is — they do go on. And for all its hefty themes and portents about stardom, and people needing people, and the Ultimate Irony of having everything and nothing, Buyer & Cellar lacks the psychological depth of a Hollywood Insider’s exposé.