Elaine Cassidy (born 31 December 1979) is an Irish actress. She is best known for playing DC Dinah Kowalska in No Offence, Abby Mills in the American television series Harper's Island for CBS, Felicia in Felicia's Journey, Runt in Disco Pigs, Lydia in The Others, Amy Harris in The Ghost Squad and Katherine Glendenning in The Paradise.

Early life
Cassidy was born in Raheny, and moved with her family to Kilcoole when she was three years old. Her first role was as the title character in a school production of Pinocchio when she was five.