Peter Hartley's stoppage-time goal sent Plymouth into the League Two play-off final at the expense of Portsmouth.
In a tense second leg, the Pilgrims deserved their 3-2 aggregate win after making a host of chances at Home Park.
Argyle's Graham Carey had an early shot tipped over while Jamille Matt missed three second-half chances and Jake Jervis hit the post late on.
But Hartley bundled in Carey's corner to secure a Wembley final on 30 May against either Wimbledon or Accrington.
The victory came 20 years to the day after Argyle, then managed by Neil Warnock, beat Colchester to make the fourth-tier play-off final.
From the first minute, when Carey's long-range shot was tipped over by Pompey's on-loan goalkeeper Ryan Allsop, Argyle showed their intention.
Jervis skewed a shot high and wide towards the end of a first period low on quality and chances for either side.
But after the break the game went up a gear, with Pompey coming close through Gary Roberts and Adam McGurk.
Matt - Argyle's two-goal hero from Thursday's drawn first leg at Fratton Park - blazed over when clean through, missed with a free header and then watched as another header was kept out by Allsop in the 90th minute to set up the corner that Argyle scored from.
Pompey, who will be in League Two for a fourth successive season next term, struggled to seriously test Plymouth goalkeeper Luke McCormick.
Both cities may have fine naval heritages, but Plymouth and Portsmouth have both suffered falls from grace because of financial problems in recent years.
Argyle almost went out of business in 2011, while in 2012 the administrators were called in at Fratton Park.
And while neither side fell out of the Football League, this season is the first time both of them have had concerted efforts in the same season at getting out of League Two.
While Argyle's renaissance could begin with promotion after five seasons in League Two, Portsmouth must contemplate another 12 months in the fourth tier.
Plymouth manager Derek Adams told BSports Radio Devon: "It's a fantastic achievement for the football club. It's 20 years since we last went to Wembley and now we're going back.
"We hit the post and we had a couple of near misses, then it got nearer to the end of the game and you got worried that Portsmouth might nick one.
"But to score in the way we did has been very good for us.
"The fans were fantastic from start to finish. And I've got to say to Paul Cook that he was man enough to come in and see our lads and wish them all the best. It's not the easiest thing to do after you've been defeated but it was big of him to do that."