Relegated Northampton provided a sting in the tail of a depressing season by hitting back to force an unexpected draw.
Trailing 2-0 with 24 minutes left, it looked a certainty that Cobblers would crash to their seventh straight Division Two defeat.
But they heartened home supporters with a taste of what might follow next season, with striker Darryn Stamp and substitute Steve Morison scoring in a frenzied seven-minute spell.
Stamp volleyed home from the edge of the box after a good run and cross from Argyle old boy Chris Hargreaves and Morison scored his first for the club after Marco Gabbiadini's shot had been kept out by Romain Larrieu.
The Cobblers could even have won it at the death with both Hargreaves and Gabbiadini going close.
Cobblers assistant boss Richard Hill said: "It might have been too little too late but if we show that sort of performance next season there will only be one way to go - and that is up." Plymouth had nothing to play for and their manager Paul Sturrock was away scouting, but his side led through a 19th minute attempted cross by David Norris which bamboozled Lee Harper, and a meaty far post header by Ian Stonebridge ten minutes after the restart.
Plymouth had by far the better of the first half chances and could have been clear, if one of Paul Wotton's fierce free kicks had beaten Harper, while David Friio perhaps should have done better with a close-range header from a Norris cross.
Argyle's assistant manager Kevin Summerfield said: "It has been difficult for the players over the last three or four weeks as we have not played a settled side in any area, having an eye on our different permutations for next season."