In the film
She is first seen after the Zettabytes give up hope for a lead singer when auditioning several girls, because Sam was told she can't dance and that she needs to in order to be the lead singer.
After an outstanding audition, Loretta is accepted. But, when trying to shake her hand, Sam trips over a wire and falls right through. This shocks the three girls, who don't know about Roscoe's part in this.
In Roscoe's father's office, he shows them the equipment and even changes Loretta's outfit.