For 40 years, New Zealand's prime ministers have sat down with an oral historian for a tell-all interview, spilling insights into their political lives.
There are thousands of hours of conversation with the likes of David Lange, John Key and Helen Clark.
But no one has ever heard them, and now the project known as Political Diaries, run by the Alexander Turnbull Library, is shutting down.
NZ Herald's deputy political editor Thomas Coughlan explains more.