This is a flawed movie born of a flawed novel, but teenage girls will eat it up. Sisterhood features three young stars (Amber Tamblyn, America Ferrera, and Alexis Bledel), indulges in rampant romantic fantasy, drips with teary-eyed sentimentality, and pays a heapload of lip service to the long-since co-opted notion of girl power. Part of the trouble stems from its failure to adapt the best-selling novel by Ann Brashares; the rest of the trouble comes from its success in doing so. The novel spreads four best-friend protagonists around the globe for a summer, sending one to Greece, another to Baja, and a third to South Carolina. The girls are bound by the titular pair of pants, magically fitting jeans that they share throughout the summer. With four plots, there isn't time to fully develop any one. The result is a constant feeling of summary, saddled with four times the usual number of after-school issues. Tamblyn is a treat, playing intelligence and anger, and there are some real moments of connection between characters, but the film is hysterical with self-promotion.