The prince ended up in a packed bar at the South Sea Hotel for Sunday quiz night, and a quiz mistress who pulled no verbal punches.
The visit was kept secret, but the printed notice in the restaurant at the hotel talked of ''special guests'' who might arrive for the quiz night.
Then there were the overalls clad police examining the fire extinguisher upstairs in the hotel late in the afternoon, and more police searching in cupboards, under chairs and elsewhere.
An Internal Affairs spokeswoman said that was happening at various sites on the island as police searched for bombs or other devices in case Prince Harry decided to visit.
Then rumours circulated Harry intended to turn up for an evening not included in his itinerary, and about 6.30pm, there he was, strolling down Elgin Tce towards the local.
Stewart Island Backpackers owner Vicki Coats is a woman with no shortage of tattoos, a whistle, and a full on attitude about being quiz mistress.
While no bombs were found by security staff combing the hotel, Ms Coats treated Prince Harry to some choice expletives and enough blasphemous outbursts to rock the St Andrews Anglican church just up the hill, where the prince had worshipped earlier in the night.
''The Stewart Island quiz is the Stewart Island quiz - it doesn't matter who comes,'' Ms Coats said. Toning down the night would not give him the real experience.
The prince ''seemed to enjoy himself'', she said, and she had a few chats with him during the two hours he spent there.
