WATCH: Zac Efron Reveals Extremely Embarrassing First On-Set Kiss Story

It's been 20 years since Zac Efron's first on-set kiss and he's still scarred from the fishy experience. The High School Musical alum recently got candid with Elle about the moment he realized he'd made a mistake after locking lips with Summerland co-star Kay Panabaker.

“I was real young. It was my first kissing scene. It was on a show called Summerland and I didn’t realize that eating fish right before that was probably not a good idea."

The actor, 16-years-old at the time, went through with the kiss with little regard to how his breath might smell and how unpleasant the kiss would be for Panabaker.

"And I kissed my costar and she went, ‘Did you eat fish for lunch?’ and everybody laughed. I’m scarred for life.”

Efron has relived this moment in a handful of interviews since 2004, each time citing cringe-worthy, fishy breath embarrassment at the misfortune of Panabaker's lips.

The standout just released his latest film, A Family Affair, starring alongside Joey King and Nicole Kidman where he plays a selfish actor turned lover boy. King, sitting by his side when he revealed the story of his first on-set kiss during the interview, agreed that the moment sounded pretty embarrassing.