Napier grew up in the city of
Lower Hutt and was educated at
Hutt Valley High School. He is the father of James Reuben Napier, actress
Jessica Napier, and Rose Napier. He is the uncle of film director
James Napier Robertson. Before becoming an actor, Napier worked variously as a labourer, factory hand, and truck driver. He also spent a year studying graphic design at the
Wellington Polytechnic. He landed his first professional acting job in 1975, at Wellington's
Downstage Theatre. In 1988, he moved with his wife and two young children to Australia, hoping to further his acting career. He soon became an established name in film, theatre, and television. His play
Freak Winds has been performed in Australia, New Zealand, United States and Canada; other plays have been broadcast on Australia's
ABC radio. His starring role in
Bellbird (2019) resulted in the film receiving awards at several international film festivals.{{cite web |title=MACAO 2019 Awards Kirill Mikhanovsky's Give Me Liberty wins the fourth International Film Festival & Awards‧Macao == Death ==