Dancy was born in Stoke-on-Trent, the son of eminent British philosopher Jonathan Dancy, a professor at the University of Reading and the University of Texas at Austin. His mother, Sarah, is a publisher. He has a brother, Jack, and a sister, Kate. Dancy was educated at Winchester College and St Peter's College, Oxford.

Dancy's first small-screen appearances were in Trial & Retribution II, Dangerfield, The New Adventures of Robin Hood and Kavanagh QC. He is fluent in French, and played a Frenchman fascinated by knights in Relic Hunter. He played the lead in BBC's Daniel Deronda (2002) which was an adaptation of George Eliot's novel based on a young man learning about life, love and ultimately who he really Read more...

He is currently dating Claire Danes. In the February 14th, 2007 edition of New York Post in which he said, "I am, however, seeing Claire. And today I live in New York, downtown, which I love". They met in London. He also stated in a recent interview to Marie Claire magazine, "I met her then, but we didn’t start dating until filming finished." His previous long term girlfriend was UK artist Read more...