She had roles on Scandal, Private Practice, House, Perception, Friends (as one of Joey's sisters), ER, Dream On, and Ringer.
She performed in theater productions both in New York City and Los Angeles, including in "God of Carnage" and "Yellow Face," as well as Christopher Durang's "Beyond Therapy".
Gagnier completed the Hallmark movie Kiss on Candy Cane Lane and The Stalker Club for Lifetime with fellow soap vet Maeve Quinlan.
On the big screen, she made her debut in New World Pictures'cult classic Girls Just Want to Have Fun, Gun, Son of an Afghan Farmer, the cult film Free Enterprise, The Undertaker's Wedding, and Breakout.
Gagnier finished the pilot "A Family Affair" opposite Pete Gardner, as well as on Brat's YouTube show Chicken Girls and Baby Doll Records as the evil Robin Robbins, where she completed Season 3.