A Kurt Weill Discovery in Covent Garden LONDON - A small girl and boy play with their toys before falling asleep, and when they have done so, the toys come to life. Adventures ensue as Evil is battled, with Good duly prevailing and the toys returning to their former inert state. This is not, as you might think, "Toy Story 17," but a new children's show at the Royal Opera House's Linbury Studio Theater that boasts an almost-forgotten score by none other than Kurt Weill. Tristram Kenton Magical Night Toys come alive for two children in a fable with music by Kurt Weill not staged since the 1920s but revived and updated at the Linbury Studio Theater, Covent Garden, London. When he was 22 Weill wrote "Die Zaubernacht" ("Magical Night") as a children's pantomime in 1922, six years before his collaboration with Bertolt Brecht on "The Threepenny Opera" brought him an international reputation. It was Weill's first work to be performed onstage, and it was a success at its premiere in Berlin, traveling to New York in 1925 before disappearing into obscurity. In 2005 a set of orchestral parts was discovered in the Yale University Library, and the Royal Opera House staging, by the choreographer Aletta Collins, is the first theatrical presentation of "Magical Night" since the 1920s. The new version sticks fairly closely to the original scenario provided by the work's first choreographer, Vladimir Boritsch, although Ms. Collins has added some new details; the set design, by Rachael Canning provides a children's bedroom of gaudy bunk-bed modernity that might have surprised Weill. This updating seems perfectly legitimate, since the point was not to recreate the original but to bring the score to life. The Weill Foundation says on its Web site that "directors and choreographers are encouraged to create their own scenarios." Ms. Collins's vivid production certainly gives it an outing, but despite the energy that the performers bring to their roles and the cleverness of some of Ms. Canning's sets, the score feels subservient to the onstage antics and thin story, and the music's dissonant textures are mostly obscured by the cheery brightness of the presentation. The musical shape of the piece is slightly strange, with just one aria close to the beginning, and quirky moment-to-moment mood changes. These present problems for the choreographer as she tries to establish an obviously dark mood for the witch, who provides the drama of the tale when - shades of "Hansel and Gretel" - she captures the little boy in order to eat him. "Magical Night" begins with the children, Megan and Jason (on Thursday afternoon, Daisy Comerford-McDonald and Alexander Adams-Camacho), playing with, then fighting over, their toys. Jason's favorite, Chimpy, has his tail pulled off by Megan, and an annoyed mother puts them to bed, stuffing the toys in a chest. As midnight strikes, the Pink Fairy emerges and brings the other toys to life with her song, nicely performed by the soprano Yvette Bonner, perfect for the part with Barbie-long blond hair and a pink tutu. Among the newly lifelike toys are Tumble Tot (Alessandra Ruggeri), an adult-size flexible baby in a romper; Sir Green Knight (Greig Cooke), who bursts out of a cupboard with stiff fencing moves; Mighty Robot (Owen Ridley-DeMonick), who emerges behind his poster above the chest; and Fire Flame (WeiChun Luo), a martial-arts, high-kicking warrior girl. Most important is Chimpy (a stand-out Thomassin Gulgec), who springs out of the chest and cavorts with break-dance-influenced smoothness before sulkily realizing that his tail has gone. That realization provides the springboard for the plot, as he turns on Megan, causing her to withdraw from the cavorting toys and draw a witch, who rapidly comes to Roald Dahl-esque life. The white-sketched-on-black kitchen scene that follows, as the witch, oddly named Sarah Good (Lorena Randi), lures the little boy into her cooking pot, is a triumph of design, and Ms. Collins manages to inject a little humor as Mighty Robot distracts Sarah in a romantic dance. The happy ending, however, like much of the opening section, feels slightly formulaic, the choreography is often repetitive, and the show as a whole has - at least from an adult point of view - little of the sophistication and captivating magic of William Tuckett's "Faeries," last year's Christmas production at the Linbury. And although the 10-member orchestra, led by James Holmes, played with lively nuance, the music felt slightly overpowered by the cartoonlike action onstage. That didn't matter to the greater part of the audience - the children. And for those who want to hear Weill's music, there will no doubt be a recording soon enough.