Waikato road policing manager Freda Grace was saddened by the crashes that had occurred in her patch.
Police are calling for witnesses of the double fatal at Horotiu just before 10pm on Friday night.
The 64-year-old man and his 51-year-old partner, both from Auckland, were travelling south in a BMW when they tried to overtake a truck and collided head-on with a northbound Toyota Corolla being driven by a 17-year-old Hamilton man, Mrs Grace said.
Police are looking for the driver of a light-coloured SUV travelling in front of the BMW - and which successfully passed the truck about 500m south of Te Kowhai township - to help them with their inquiries.
"We think the SUV had overtaken the truck and the BMW has gone at the same time and that's when the crash has occurred."
Conditions were drizzly and dark at the time, she said.
The 51-year-old woman remains in a serious but stable condition in Waikato Hospital.
In relation to the first of two crashes at the Karangahake Gorge just after 10am, a westbound VW Passat carrying its 22-year-old female driver and two male passengers of similar age appears to have lost control in wet conditions and struck the barrier and travelled about two vehicle lengths before it over-corrected, crossed the centre line and collided head-on with a Ford Festiva being driven by a 69-year-old Cambridge man.
The 22-year-old and her passengers managed to walk away from the crash, Mrs Grace said. The Cambridge man was airlifted to Tauranga Hospital and remains in intensive care.
Mrs Grace said the second crash was remarkably similar. A 19-year-old Hauraki man lost control on the apex of a corner, crossing the centre line and colliding head-on with a car being driven by a 48-year-old man with his 17-year-old daughter in the passenger seat, she said.
Both men were airlifted to Waikato Hospital with serious injuries. The 19-year-old remains a critical condition in intensive care, and the 48-year-old man is in a serious condition in the high dependency unit.
Mrs Grace said the crashes were a result of motorists "not adjusting their driving to the roading conditions and the weather".
Mr Greally said the driving culture in New Zealand had to change if the road toll was to abate.
"Responsibility for the safety of the remainder of this holiday weekend sits purely with each and every driver on our roads. New Zealand police will be there, but ultimately responsibility is only with the driver and nobody else. It's so unnecessary.
"The New Zealand culture on our roads needs to modify so that it's almost by peer pressure that it's unacceptable to others."
