Beeby and Sewell were directly responsible for saving at least two of the diplomats, Campbell White told Kathryn Powley of the Herald on Sunday after the film was released.
She described how the New Zealanders and four US diplomats had been on a camping excursion in the days before the embassy was stormed.
On the way back, the vehicle carrying the Americans broke down. It was late so they dossed down on the floor of Campbell-White's place.
In the morning, when they learned the US embassy had been stormed, Beeby came to take the diplomats to the New Zealand embassy, hiding them under blankets in the back.
Two of the four decided to go it alone but the other two remained hidden in the embassy's safe room which was out of bounds to the Iranian cleaner.
"It had big Chubb doors because our coded cable machine was in there," Campbell-White told Powley.
But the New Zealand embassy was considered too risky to keep them for long.
"We had to be very, very careful. Christopher didn't take them to his residence because he had two cooks, cleaners, a butler and gardeners. The New Zealand Embassy residence was a big compound so there were lots of locals working there."
So they were taken to the Canadian embassy which is the focus of the film.
But the Kiwi role was not over. It was Sewell who drove the escaping diplomats and their CIA minder - Tony Mendez, who went under the code name Kevin - to the airport.
Powley reported that in his diary Sewell describes how he collected "Kevin" from the Sheraton Hotel after a late farewell dinner.
"The night was silent - none of the small-arms fire or night-time chanting we had got used to during the revolution. Now there were other problems ... Komitehs [revolutionary committees], road blocks, trigger-happy revolutionaries firing off their weapons."
Despite running late they got to their destination on time.
"I asked Kevin whether he had ever pondered what would happen if all this went wrong," said the diary. "'I suppose we'll all be down at the Embassy with the rest,' he replied. 'Maybe I'll even be shot'."
Until Argo, the only public hint of New Zealand's Tehran heroes came at Sewell's funeral in 1989. "There's stuff we can't talk about at this point in time but it will come to light that Richard played a heroic role," said Beeby.
And now that it has come to light and we can talk about it, Christopher Beeby and Richard Sewell are our New Zealanders of the Year for 1979.
From the Herald archives:
'Affleck movie dumps on NZ', NZ Herald online, 17 October 2012
'NZ survivor of hostage crisis breaks silence over Kiwi heroism in Tehran', NZ Herald online, 17 March 2013
'More details on Argo rescue revealed in diary', NZ Herald online, 31 March 2013
