Two of the proudest and best supported clubs in the league, South Sydney and Canterbury, have only faced off in a grand final once before, way back in 1967 - a match won by the Rabbitohs.
Souths are chasing a first premiership in 43 years, but the Bulldogs will be no less hungry having gone 10 years without a title.
Former Bulldog Idris had a forgettable night.
The big centre grassed a perfectly-placed cross-field kick shortly after the break which would have led to the Panthers equalising at 12-12.
Then a silly intercept let the Bulldogs off the hook and resulted in Canterbury extending their lead to two converted tries.
With four minutes remaining and Penrith deep on the attack looking to push the game to golden point, Idris was crunched by opposite number Tim Lafai and coughed up possession.
The Panthers never got another chance.
Englishman Graham sensed his side was losing their grip on the contest early in the second half, despite being up 12-6 on the scoreboard, and decided to get in the face of Penrith lynchpin Jamie Soward.
Canterbury prop James Graham was an inspirational figure for the Bulldogs throughout the match. Photo / Getty Images
The intimidation tactics appeared to work as the Panthers bumbled several attacking chances, before Corey Thompson latched onto Idris' intercept pass and turned defence into attack for Canterbury.
Penrith forward Lewis Brown produced an extraordinary try-saving tackle on Sam Perrett.
But the Bulldogs weren't to be denied and on the next set after a drop-out, Greg Eastwood poked his head through the line and sent Dale Finucane over for the decisive try which put Canterbury up by 12 with 22 minutes remaining.
Canterbury's dummy-half play was stop-start without Ennis, but they will face a South Sydney side next week who could also be without their No 9 - Issac Luke facing sanction over a dangerous throw.
For the eighth straight week the Bulldogs failed to score more than one try in the second half, but in successive finals' wins over Melbourne, Manly and Penrith - their defence is what's got them home.
Penrith couldn't get rid of their nerves early in the match and never played with any convincing structure, allowing Graham and Josh Jackson to put Canterbury up 12-0.
With seven penalties in the opening 13 minutes, and 11 for the first half, the Panthers managed to get some calls heading into the final few minutes and golden boy Matt Moylan crossed with a minute left before the break.
-AAP