Timid Catholic school dork Edie Arnold is dragged to a punk show where a mishap lands her on stage behind the drums. She's mortified... but a natural. Convinced by her best friend, she secretly forms a band called The NunDead. Her newfound confidence leads to a date with the altar boy but also a fight that gets her suspended. Thinking she bailed on their first gig, her bandmates bust her out of the house just in time to win a Battle of the Bands. But when she faces expulsion and her mother's wrath at a disciplinary hearing, footage of her kick-ass performance has an unexpected effect on her mom.