Nothing could separate the sides, with the match evenly balanced at 2-2 after 120 minutes and 2-2 after the first round of penalties.
However, Ronald Ross was the difference, hitting the winning penalty after Kings goalkeeper Craig Dawson saved from Fort’s Arran MacPhee.
The Badenoch side will now play the winners of next weekend’s clash between Skye and Glen Urquhart.
“It was a rollercoaster of a game,” said Ross. “It is never nice to win on penalties but we will take it. We need to regroup now and focus on the final. It means everything for us to be there.”
After only two and a half minutes, Kingussie’s Barry Dallas found himself outfoxed by a bad bounce on the bone-like surface and, suddenly, Fort were in the driving seat.
Bryan Simpson, a player with several Camanachd Cup winners’ medals, was first to react and shot low, and at an angle, past the helpless Craig Dawson in the Kings goal.
That counter set the pattern, with the yellow and blacks continuing to deliver the ball into fiery areas where defenders were less than comfortable with the cross-field blasts.
For Kings to get a foothold in the game, it was going to take someone to hold the ball up front and bring others into creative play. Either that, or it would take something beyond the ordinary.
They got the latter and from the caman of who else but Ross, MBE.
Fraser Munro performed a neat pirhouette on the edge of the area and when his intended pass broke off a defender’s stick, Ross was on it like a viper and the ball was ruffling the net before you could shout “shoot”.
Kingussie needed that interjection but they couldn’t hold on long enough. Fort striker Daniel Stewart was afforded too much time to turn in 29 minutes, shrugging off lacklustre defenders. Keeper Craig Dawson’s facial reaction told the story as the ball appeared to bounce in under his stick after Stewart shot.
Fort, abetted by the gale, were definitely in the ascendency but they left the field at half-time with the scores at 2-2 thanks to a wonder strike by Kingussie’s Savio Genini. With four minutes to go until the interval Genini found himself in space on the left-hand side of the goalmouth.
The youngster took his time, teed up the ball and curled it high into the top corner of the net. It was a strike worthy of such an occasion and may be a contender for goal of the competition.
Kings were playing with the wind in the second half but it was the home side who came closest to a lead. A ball which spun across the penalty area was missed by Dallas in 61 minutes and Simpson clipped a shot off the post after doing everything right.
The home fans couldn’t believe it and, after that, the game seemed to stabilise, seeking ignition. That did not come in normal time, despite some late Kingussie pressing, and, suddenly, it was all about who could last the distance.
For the second time in Cup competitions this season, the combatants would take extra time to sort out their differences.
Fort William, with the west coast wind behind them again in the opening period of extra time, took the game to Kingussie, perhaps knowing a goal at this stage would be enough.
But creativity was suffering at the expense of tiredness, both mental and physical, with several players hobbling and nursing bloodied scars.
The analogy of the chess match, at this stage, was appropriate and the contest was begging for something unique to separate the teams.
A second yellow card for Fort’s Neil Roberston may, under normal circumstances, have been a deciding factor, but there were fewer than three minutes left when he up-ended Thomas Borthwick and it was penalty hits time.
Kings kept their cool and now have the chance to win their first Camanachd Cup since 2006.