Shackelford has also played roles in Wonder Woman and most recently in The Division. He also starred in the British science fiction series, Space Precinct. On February 2, 2006, he joined the cast of the daytime soap opera The Young and The Restless as Genoa City district attorney William Bardwell. His last air date on the popular soap as William Bardwell was on July 18, 2007, when his character succumbed to complications caused by a stroke. However, on August 7, 2007, Shackelford returned to the show as William's identical twin brother, Jeffrey Bardwell.