Besides physics, the branch of science most attractive to writers is biology, especially where it deals with inheritance and sex. Brighde Mullins' new play accordingly stirs a little neo-Darwinism into the story of a teenage castaway. Tara Scanlon, "who is big for her age," has to contend with Vegas-area bars and straying geneticists after her Marine father abandons two of his children in the Mojave Desert (to toughen them up). The straying geneticist in question is Henry Kropotkin, or "Copenhagen," who can seduce women by removing his sunglasses. He picks up Tara in a bar and drives her around the desert, like Nabokov's Humbert Humbert, while his colleagues try to convince him to return to a normal university career. Copenhagen finds the solution to his highest theoretical problems in Tara, and Tara finds a smart and sensitive father figure in him. The play, unfortunately, is an overly clever contraption: Not much emotion filters into the audience, even when the acting is strong. Kathryn Pallakoff does well enough as Tara, but in a preview performance Hank DiGiovanni and Molly Goode played her parents stiffly, and Rhonnie Washington was an unseductive Copenhagen. Amy Resnick was very funny as a straight-laced caseworker getting blind drunk on a bottle of chardonnay, but most of the show was too scattered to leave much of an impression -- about Darwin or sex or anything else.