Celebrity Jessica Biel Can Sing! Watch Her Break Into Song on the Red Carpet By Kelsey Glein Kelsey Glein Twitter Kelsey Glein is a Seattle-based writer and editor who covers all things fashion, beauty, and pop culture. She was previously the Digital Editor of InStyle and is currently a Social Media Manager at a cosmetics company. InStyle's editorial guidelines Updated on January 11, 2017 @ 08:00PM Pin Share Tweet Email Photo: Jason LaVeris/FilmMagic Who knew Jessica Biel had such a set of pipes? The actress broke out in song at the premiere of her new movie The Book of Love in Los Angeles last night, where she belted out an impromptu version of "Happy Birthday" during an interview on the red carpet. And while we were mesmerized by her skills, the 34-year-old was quick to refer to her singing as "bad musical theater." VIDEO: Jessica Biel and Justin Timberlake's Cutest Couple Moments But if you were hoping that this means there's a future duet in store for her and husband Justin Timberlake—who has won a whopping nine Grammy Awards—Biel says think again. "Oh my god, please stop," she said when the idea was proposed. "My mother won't stop with the duet. I'm like, 'Mom, it's not going to happen. It's not going to happen, Mom.'" But she did reveal the exception to the rule. "Maybe in the shower," she shared. "Well, not really. It's more like the bedtime routine, like singing the baby to sleep—that's really where the duets happen." Awww. Jessica Biel Still Hasn’t Found a Flaw in Justin Timberlake Watch Biel sing her heart out in the clip above.