Plymouth limited Cardiff's lead at the top of the Second Division to just one point when Graham Coughlan equalised with the very last kick of the game.
Confident City had looked to be cruising to a deserved victory with two goals from Robert Earnshaw, in the second and 67th minutes, either side of Paul Wotton's eighth minute free-kick.
But City, who nevertheless extended their unbeaten away run to 12 games, were stunned by Plymouth's never say die attitude which resulted in two late corners, and a goal which manager Lennie Lawrence was sent off for disputing.
Neither side showed any change from the line-ups that suffered contrasting fortunes on Saturday. Plymouth manager Paul Sturrock gave a vote of confidence to the players who lost 1-0 at home to Chesterfield while Lawrence sent out the same starting eleven for the fourth game in a row.
Cardiff got off to the perfect start when Earnshaw took advantage of home captain Wotton's miscued header to put the visitors in front after only 84 seconds.
Wotton made amends for his error six minutes later, after Danny Gabbidon fouled Micky Evans 35 yards from goal. The Plymouth skipper stepped up to drill home his fifth of the season past goalkeeper Neil Alexander.
If Alexander looked at fault for the goal, he redeemed himself with two world-class saves later, keeping out Hasney Aljofree's free-kick and then clawing away a goalbound header from Evans.
Ian Stonebridge hit the post for the home side and Coughlan blocked a drive from Cardiff's Gareth Whalley as the all action game swung from end to end.
Cardiff, however, gradaully assumed control of the second half wore on and it was not surprise when Earnshaw doubled his own tally heading home Andy Legg's cross