They trailed by five points with a quarter of an hour to go.
Laois secured a All Ireland Intermediate Camogie semi-final birth against Antrim next weekend.
A stunning comeback win over Kerry, in which they only managed one score in the opening 45 minutes accounted for that.
The kingdom led by 1-5 to 1-0 with fifteen minutes remaining in the contest, a solitary Sara Cuddy goal the only mark on the scoreboard for the O'Moore women.
However John Desmond's side showed great heart in terrible conditions, tagging on five points without reply in the closing stages to force extra-time.
Two Clodagh Tynan points in injury time proving crucial.
They took control in the additional time, Kirsten Keenan was immaculate from frees throughout the day, top scoring with four points.
Laois dominated, going on a five points to one run to leave the scoreline 1-10 to 1-6 in their favour after the extra period.