Seth Gabel was born on October 3, 1981 in Hollywood, Florida. He graduated from New York's University Tisch School of Arts. On June 17, 2006, Seth married actress Bryce Dallas Howard. They had a son on February 16, 2007 and named him Theodore Norman Howard.
His acting career began with several guest star roles on TV shows such as CSI, The Closer and Sex and the City. His memorable role as Adrian Moore, the sexually ambiguous son of Famke Janssen's character in Nip/Tuck, garnered him much attention. In 2006, he appeared on the film version of The Da Vinci Code directed by his future father-in-law Ron Howard.
In 2007, he acquired his first regular series role as Jeremy Darling, the fraternal twin sister of Samaire Armstrong's character, in ABC's Dirty Sexy Money.
He went on to be a recurring character in the TV series Fringe, where he later went on to become a regular. Gabel can also be seen playing the character Count Vertigo in Arrow.