Charlton had previously swept aside Leyton Orient with a spectacular 5-0 win and then beaten Peterborough with a 2-1 win. Fans were confident of another win, but from when the match started Plymouth were playing the better football.
Plymouth scored with a penalty from captain Paul Wooton on the 34th minute and a stunning strike from David Friio six minutes after the interval.
But Charlton hit back with a strike from Shaun Bartlett 12-minutes from time and a controversial penalty decision, which was cooly converted by Euell 5-minutes from time.