Actor Isaiah Washington is set for a return to the medical drama he was forced out of following a gay slur scandal in 2006. The star left Grey's Anatomy in disgrace in 2007 after it was alleged he upset gay co-star T.R. Knight during an on-set argument by calling him a derogatory homophobic word. Washington apologised for his "unfortunate use of words" but his contract was not renewed by producers at the end of the show's season three, and the actor left the series. He will return as Preston Burke for one of Sandra Oh's final shows - his doctor previously romanced Oh's character Cristina Yang. Grey's Anatomy creator says, "It's important to me that Cristina's journey unfolds exactly as it should. Burke is vital to that journey - he gives her story that full-circle moment we need to properly say goodbye to our beloved Cristina Yang."