Another from the previously reading pile.
From the Blurb:
When Dean Bradley is brutally murdered for his new shoes, undertaker Ken Tamati does a lovely job on the corpse — but next morning, the body has vanished from the funeral parlour.
That day, a mysterious figure — witnesses give wildly conflicting descriptions — begins rescuing victims of assault all over Auckland and healing their horrific injuries with a dazzling light. They call him the Rainbow Man.