Recalling Paul Greengrass’ Bloody Sunday and Pete Travis’ Omagh, Out of the Blue’s documentary style and refusal to play the standard serial killer thriller game makes for shattering viewing.

Director Robert Sarkies patiently introduces the main players on the fateful two days between 13th and 14th November 1990 and the idyllic seafront town of Aramoana where the massacre occurred.

Tension escalates as it becomes obvious these people live in the same neighbourhood as David Gray (Sunderland), a local man mildly harassed by the police and ready to explode.

Everyday events such as a beach outing or walking the dog take on added poignancy when placed beside Gray’s heated argument with a bank-teller over a $2 charge or his paranoid delusions in a ramshackle house.

When the shooting starts Sarkies depicts it matter-of-fact, from the standpoint of passer-bys or those observing from a distance, keeping the volume of the killer’s weapons to almost comical pops.

Gray murdered children and old people without hesitation and the crisp, no-nonsense camerawork does not shy away from the horror but resists dwelling on the carnage.

Professional and non-professional actors give terrific performances. Standouts are 74 year old first-timer Lawn as Helen Dickson, a woman who crawled home through a drainage ditch to call an ambulance for a wounded passer-by before crawling back to the man; Urban, unrecognizable beneath a $7 haircut and 'tache, as an under-prepared policeman on the scene; and Sunderland, both sympathetic, twitchy and terrifying as Gray.

As night draws in and the well-prepared gunman faces off against jittery policemen and armed response, while frightened residents cower in their houses, Out of the Blue criticizes the system that allows seemingly everyone to own rifles but is unprepared for a mass shooting.

The filmmakers were originally lambasted for planning to recreate the tragic incident, but Sarkies and his cast and crew won the trust of survivors and families with their sober and humane treatment of the material.

In no way an easy watch, but as a meticulous record of a tragedy and the feats of bravery it inspired, this is an excellent movie.

Rob Daniel