Henry Ian Cusick was born on April 17, 1967 in Trujillo, Peru. His mother is Peruvian, and his father is Scottish. He was brought up as a Roman Catholic, and speaks fluent English and Spanish. As a young boy, Cusick grew up in Trinidad and Tobago, and then moved to Scotland when he was fifteen years old.
Cusick studied at the Royal Scottish Academy of Music and Drama in Glasgow, Scotland. Soon after, he joined the Citizens' Theatre, and it wasn’t long before he was constantly performing on stage in Great Britain. He began taking roles in television and film as well, including the role of Jesus, in The Gospel of John
(2003). In 2005, began a recurring role as Desmond Hume, on the drama series, LOST
(for which he was nominated for an Emmy in the category, "Outstanding Guest Actor in a Drama Series") and is currently a permanent member of the cast. He also had a recurring role on FOX’s series, 24
Cusick and his wife, Annie, were married on July 15, 2006 in a civil ceremony, though they had been living together as a couple for fourteen years. They have three sons, named Elias, Lucas and Esau.