Matthew Macfadyen hoped to return to Ashes to Ashes

According to the Mirror

Matthew Macfadyen's hopes of appearing in Ashes To Ashes again have turned to dust. The hubby of Keeley Hawes, who plays Alex Drake, guested as oddball charity worker Gill Holis in the first series. He said: "I pleaded for another part. But once you're in it, you can't do it again."
Thanks to fleurdlis for finding the article.