He trained for a year with the Auckland Theatre Company at the prestigious Globe Theater in London.
[1] He then attained his Bachelor of Performing Arts at Toi Whakaari: New Zealand Drama School in 2006.
He has gained recognition through musical theatre, receiving positive reviews for his role as William Kemmler in the Indian Ink production of The Dentist's Chair.
Shannon Huse, reviewer for the New Zealand Herald, wrote "Gareth Williams is suitably cadaver scary as William Kemmler, the ghost of the first man to be executed by electric chair who haunts Albert.
[4][5] Williams landed the supporting role of Vettius in Spartacus: Gods of the Arena (2011).