Half of the comedic act 'Armstrong and Miller' with Alexander Armstrong. He has also acted on ITV's science fiction program me Primeval and on the crime drama series Death in Paradise.
He was studying for a Ph.D. in quantum physics at Cambridge before moving to London to pursue a career in comedy. He and Alexander Armstrong performed their first full-length show at the Edinburgh Fringe in 1994.
He received a 1996 Perrier Comedy Award nomination along with his partner Alexander Armstrong.
He had a son, Jackson, in 2006 with then-wife Belinda Stewart-Wilson. He has two younger sisters, Leah and Bronwen and his father Michael was a lecturer in American Literature at the City of Birmingham Polytechnic.
He co-starred with Julia Stiles in the 2004 film "The Prince and Me."