A leading if somewhat uneven figure among the glories of New Zealand cinema who made his mark in the 1980s, director-writer-producer Murphy became a hired gun in the first capacity in Hollywood action fare of the 90s. A former teacher and published author, he earned an early credit working on special effects for the political adventure, "Sleeping Dogs" (1977). Murphy made his screenwriting, directing and producing debut with the car chase action comedy "Goodbye Pork Pie" (1980). Although the antics of the protagonists were more crude and rowdy than genuinely witty or provocative, the film had energy, was technically playful, and scored a huge hit both in New Zealand and abroad.
Murphy's reward was the most expensive production undertaken to that date in New Zealand, "Utu" (1982). Another boisterous adventure indebted to traditions from the spaghetti Western, it used violence, deadpan comedy and thrilling action set pieces to render a remarkably rich historical tapestry about a renegade Maori tribesman who vows revenge on the British army that decimated his native village. "Utu" was also a success, allowing Murphy the chance to further explore his interest in New Zealand's indigenous population by producing "Patu!" (1983), a documentary by Merata Mita, and consulting and acting in Mita's psychodrama "Mauri" (1988). His own penchant for the outlandish also continued in his own films, especially the intriguing fantasy "The Quiet Earth" (1985) and the action comedy "Never Say Die" (1988).
Murphy's ebullient and commercial talent meant that a chance to work in Hollywood was inevitable, but as of 1996, he has been somewhat confined to rather conventional genre fare. "Young Guns II" (1990), as sequels go, was not bad, with strong visuals bolstering a hackneyed storyline. A reteaming with that film's star, Emilio Estevez, for "Freejack" (1990), a muddled sci-fi thriller, was hardly redeemed by its occasional technical pizzazz. Murphy followed with another sequel, "Under Siege 2: Dark Territory" (1995). No longer writing or producing his own directorial efforts in the Hollywood division-of-labor system, Murphy clearly enjoyed the production facilities at his command, but his work overall has been less distinctive than his best New Zealand efforts.