Brisbane captain Adam Reynolds stepped up in the biggest moment of his career to end Penrith's five-peat dream with a stunning 16-14 comeback victory.
The Broncos' win in the preliminary final has set up a grand final showdown with fierce rivals Melbourne.
Reynolds landed a sideline conversion in the 77th minute to win it, putting to bed the demons of missing from the sideline to level in the dying minutes in the 2021 grand final against the Panthers, while playing for South Sydney.
The Broncos, trailing 14-0 at halftime, shocked the four-time defending premiers at Suncorp Stadium on Sunday.
It was a redemption story for the ages for 35-year-old Reynolds who had also copped criticism for not getting the Broncos over the line in the 2023 grand final, won by the Panthers 26-24 thanks to the genius of Nathan Cleary.
The Broncos are never beaten. They have come back to win this year after trailing by 18 points, twice from 16-points and on another occasion from 14 points behind.
The home side secured their 12th win in the past 14 matches on the back of a brilliant second half.
The first big play came from back-rower Jordan Riki who stopped Nathan Cleary on the tryline when the visitors appeared set to go up by 20 points.
Reynolds, returning from a seven-week layoff with a hamstring injury, laid on a try at the other end for centre Kotoni Staggs with a deflected grubber.
Brisbane repelled raid after raid before prop Xavier Willison charged over in the 70th minute.
Fullback Reece Walsh, in traffic, set up winger Deine Mariner in the 76th minute and the impossible was all of a sudden possible.
Walsh had missed the previous conversion and handed over to Reynolds for the sideline winner, which he slotted with composure before standing in front of the crowd and soaking up the adulation.
The Panthers dominated the first half with two tries to winger Paul Alamoti.
Cleary was in control and it appeared certain he would guide them to a sixth grand final in a row.
Reynolds and the Broncos had other ideas.
The hosts missed the impact of suspended lock Pat Carrigan in the first half but they rallied in the second.
Payne Haas carried the side on his back to get the Broncos back into it.
He was back in the in-goal area to clean up one grubber kick and charged ahead relentlessly to inspire his teammates.
The Broncos have played the Storm once before in a decider in 2006 and triumphed 15-8.