It's not a cliffhanger from Shortland Street, New Zealand's longest-running TV soap opera, but a real-life tale of abandonment.

It happened back in January 1973 to the South Pacific nation when the UK joined the then European Economic Community (EEC), the precursor to today's European Union.

At the time, about half of Kiwi exports were shipped 18,500 km (11,500 miles) to the UK, but access to those prized markets would effectively end as a result of the UK joining the EEC.

"It was a massive shock. It was an emotional shock for New Zealand," says Asha Sundaram from the University of Auckland.

"Almost 50% of New Zealand exports went to the UK at the time, and so there was huge anxiety about what would happen.

"Essentially New Zealand was like an outpost of Britain [back then]. It was this parent-child relationship, and I think people were just terrified of the apron strings being cut off.

"I think it was probably panic."