Trailing by six points at the final break, the Kangaroos' historic 25-match winning streak looked in danger after a scoreless third quarter in Saturday's preliminary final at Ikon Park.
Needing the first goal after the break, Irish star Blaithin Bogue answered coach Crocker's call to kickstart the comeback for North's sensational 6.10 (46) to 5.6 (36) victory in front of 7057 fans.
The Roos, looking to become the first women's side to claim back-to-back premierships, next face the winner of the Brisbane-Carlton preliminary final.
Crocker concedes the Demons had posed their biggest challenge so far.
"Prelims are sometimes really hard games to get through because you know what's on the end of a prelim win," Crocker said.
"You go into, sometimes, a prelim with a bit of anxiety around trying to get through that game and make the grand final.
"Now we've made the grand final, so players can feel a bit freer."
After kicking two crucial goals in the first term, Bogue had launched North Melbourne ahead by two points before captain Jasmine Garner hit the scoreboard herself to steady the side.
Garner (one goal, 32 disposals, seven clearances) and fellow midfield superstar Ash Riddell (one goal, 24 disposals, three clearances) saw plenty of the ball, as Emma Kearney led a tough North Melbourne defence.
Superstar captain Kate Hore (two goals, 18 disposals) was nothing short of sensational against North Melbourne, but her effort wasn't enough.
Maeve Chaplin (22 disposals), Eliza McNamara (21) and Paxy Paxman (one goal, 15 disposals) were similarly busy for the Demons.
Demons coach Mick Stinear said his side simply ran out of steam..
"We were just hanging in there and thought we defended really well, but then that dam wall sort of broke towards the end," Stinear said.
"Their quality stepped up and having the week off probably showed in those dying minutes."
Melbourne had stunned the hosts with a lethal opening display, kicking the first two goals within five minutes while keeping the defending premiers to a team-wide two disposals.
The Demons then broke out to a 19-point lead halfway through the first quarter before North worked their way into the game through Bogue's two-goal haul.
Melbourne wrestled momentum back by quarter-time when Tayla Harris slotted the final goal before lighting up Ikon Park with a sensational mark against Riddell.
The Kangaroos started the more daring side after the break, with league best-and-fairest favourite Riddell's goal launching the hosts ahead.
But the defending premiers' ascendancy extended as much as two points before the Demons reversed the margin courtesy of a 50-metre penalty to Hore from North forward Bella Eddey for infringing the protected zone of the opposition captain's mark.
North Melbourne's two-point deficit at halftime was the first time they had trailed at the main break this season.
A desperate Kangaroos side were then held scoreless in a tight third quarter as Melbourne managed just four more points on the scoreboard before the final term.
