On the heels of their first backstage video, “Forget You,” the ladies of Baby It’s You decided to put their spin on another current pop hit, Rihanna’s “Only Girl.” Erica Ash provided lead vocals, with Kyra Da Costa, Christina Sajous and Crystal Starr joining in perfect harmony. Step into the stairwell at the Broadhurst Theatre and listen to Broadway’s Shirelles show off their real-life pop skills.