Morrissey was cast in the television series "One Summer" (1983) at the age of 18, and subsequently attended the Royal Academy of Dramatic Art before acting with the Royal Shakespeare Company and National Theatre for four years. Throughout the 1990s, he often portrayed policemen and soldiers, though he also played Bradley Headstone in "Our Mutual Friend" (1998) and Christopher Finzi in "Hilary and Jackie" (1998). He then had roles in "Some Voices" (2000) and "Captain Corelli's Mandolin" (2001), before he played the critically acclaimed roles of Stephen Collins in "State of Play" (2003) and Gordon Brown in "The Deal" (2003). The former earned him a Best Actor nomination at the British Academy Television Awards and the latter won him a Best Actor award from the Royal Television Society.