In a grandstand finish, substitute Erin King scored her second try for Ireland in the 79th minute to level the scoreline at 27-27.
Out-half Dannah O’Brien delivered the biggest moment of her young career so far to kick the clutch conversion and edge a two-point win.
A decade on from Ireland’s first ever win over New Zealand at the 2014 Rugby World Cup, Ireland have upset the world order of women’s rugby once again.
There were tears from the players at the end, including from Ireland captain Edel McMahon, as the players celebrated a win that was wholly unexpected of this developing team. Their transformation under head coach Scott Bemand and his coaching team continues at a breath-taking pace; 12 months ago they were playing in Tier 3 of this competition. And now a win in their first game in Tier 1 against the team ranked second in the world.
And once again it was Aoife Wafer – who scored two tries in the first half – who showed she is a world class-player.
The Leinster backrower was named player of the match for the second game in a row but this was also a complete team performance.
Ireland scored five tries but also put in an outstanding defensive shift including when were down to 14 players midway through the second half after Niamh O’Dowd got yellow-carded.
When Mererangi Paul scored the Black Ferns’ third try in the 73rd minute, it looked like the win was going to elude Ireland.
But this team has developed into a hard-core side. With their line-out once again the source, sevens star King completed a brace of tries in just her second 15s game for Ireland. O’Brien’s conversion went in off the post to secure an all-time great day in Irish rugby.
It didn’t look like this would be the ending at the start of this game as the Black Ferns dominated this clash and they signalled their intent from the off.
In Wafer’s first touch of the ball, the Black Ferns looked like they knew all about the Wexford woman as she was double-tackled by Maia Roos and Liana Mikaele-Tu’u and shunted back.
The women in black displayed their brilliant off-loading game and immediately put Ireland under pressure.
There was an inevitability about their first try in the ninth minute, Ireland simply couldn’t handle their line-out maul and hooker Atlanta Lolohea dotted down.
But Ireland began to find their rhythm and they capitalised on New Zealand mistakes.
After 13 minutes, Ireland won a scrum penalty inside the New Zealand 22 and fast thinking by Wafer saw her take a quick tap and despite the efforts of Layla Sae and Mikaele-Tu’u, the Wexford woman proved unstoppable as she scored Ireland’s first try.
Just the response Ireland needed. O’Brien missed the conversion.
As well as excellent line-speed, Ireland delivered moments of outstanding scramble defence including from scrum-half Molly Scuffil-McCabe after 17 minutes as she produced a brilliant try-saving tackle on Sae.
But Ireland were ruthless with taking their chances. They notched up try number two after 29 minutes in almost a carbon copy of the first. Ireland got a penalty inside the New Zealand 22, Ireland opted for a scrum and again it was Wafer who produced the goods from the base of the scrum.
While Scuffil-McCabe ran to the left, Wafer ran to the right, dummied a pass to Eimear Considine but ran over herself. O’Brien got the conversion.
The confidence in this team was visibly growing. Ireland hit the front four minutes before half-time with a try from Neve Jones to push them into a 17-10 advantage.
After Ireland kept their opponents scoreless for 20 minutes, New Zealand hit back with their second try thanks to winger Katelyn Vahaakolo just before the break to leave it 17-17 at half-time.
New Zealand will rue their disallowed tries in the second half. In the 43rd minute, they looked like they had their third try but Sylvia Brunt lost control of the ball on the grounding.
Nine minutes later, they had a try ruled out when there was a knock-on in the build-up to substitute Mererangi Paul scoring.
It was in that play that Ireland were reduced to 14 players for 10 minutes when O’Dowd was yellow-carded for deliberately pulling down the maul.
A minute later, New Zealand had a third try ruled out when Luka Connor’s effort from a line-out was disallowed for obstruction.
A Renee Holmes penalty put New Zealand in front at 17-20 but an under-pressure Ireland kept themselves in the game.
And Ireland just built from there. King made a powerful impact when she came off the bench against Australia two weeks ago and she did the same in Vancouver.
Ireland continued their trend of turning down points to kick to touch and their line-out was once again a source for tries.
In an excellent set-piece, sub Cliodhna Moloney threw to Brittany Hogan and they showed brilliant deception to move the ball back to Moloney who went close to the line but it eventually went to King to go over. Game on again.
While Paul’s try in the 73rd minute looked like the winning of it for New Zealand, Ireland showed their defiance right to the glorious end.
Again, Ireland caught New Zealand off-guard at the line-out and it resulted in King scoring her second try. Then O’Brien stepped up for the conversion. Then Ireland upset the world order of women’s rugby with a stunning victory.