Missed chances came back to haunt Dartford at Princes Park on Tuesday night.
They dominated the first half against Torquay but failed to score while on top.
The Gulls struck twice in the last 18 minutes and those goals sent them top of National League South.
New signing Dan Darbyshire made his debut for Dartford, who were without Charlie Sheringham and Elliot Bradbrook. Kudus Oyenuga got a start up front, with Jamie Philpot dropped to the bench, while Tom Bonner returned in central defence after illness.
Darbyshire lined up wide on the left, with Ben Greenhalgh playing just behind Oyenuga, and it was a partnership which looked dangerous early on.
Torquay spurned a good early opening, Jamie Reid missing his kick in front of goal, but it was Dartford who created a flood of good chances in the first half.
The pace of Oyenuga gave them an outlet every time, especially with the Gulls holding such a high line. Oyenuga flashed two crosses through the six-yard box and Torquay manager Gary Johnson was fuming at his defence when one pass from Jordan Wynter sent Oyenuga sprinting clear for a third time.
Darbyshire looked neat and tidy and he did well to pick out Andre Coker with a low cross. Coker's scuffed effort was only half cleared but Lee Noble blazed the rebound high over the bar.
Dartford looked certain to score from their next attack but unbelievable Torquay defending saw shots from Coker, Oyenuga and Noble cleared off the line.
The effervescent Oyenuga rattled one shot into the side netting and saw another deflect behind for a corner. He was taking up great positions on the counter-attack although his decision-making in the final third could perhaps have been better at times.
Torquay moved the ball quickly and posed a threat at set-pieces, with Kyle Cameron's towering header from a corner well saved by Bailey Vose.
But still it was Dartford who looked more likely to score, with Darbyshire bursting past a couple of defenders and threading a low shot narrowly wide.
The Gulls lacked potency in front of goal, with Connor Lemonheigh-Evans failing to hit the target with a powerful strike from distance and Vose collecting several tame efforts.
But the keeper had to be alert to push Ruairi Keating's angled drive round the base of his near post a minute before half-time.
It took a while for the second half to settle down and when it did, Greenhalgh's ambitious strike from wide on the right had Alex Bass scrambling on its way wide.
Bonner went straight through the back of Saikou Janneh in front of the dugouts and picked up a yellow card as Torquay started to gain a measure of control.
Oyenuga was starved of possession and Noble was getting through a mountain of work in midfield as the pressure mounted.
It told in the 72nd minute when a ball from the left sat up nicely for Ruairi Keating, who crashed a volley into the roof of the net from the right-hand side of the penalty area
Dartford looked short on ideas now, with substitute Philpot swirling a shot well wide when space opened up in front of him.
Keating missed a good chance to make it 2-0 when the ball dropped in the box and Hayes was sent on for the last 10 minutes as Dartford tried to find a spark.
But the home side were a spent force and Reid's low shot, two minutes from time, found the bottom corner to put the result beyond doubt.
Dartford: Vose, Onyemah, Vint, Bonner, Johnson, Coker, Wynter, Noble, Darbyshire (Philpot 69mins), Greenhalgh, Oyenuga (Hayes 81mins). Subs not used: Fisher, Nicholls, Gillies.
Torquay: Bass, Wynter (Sendles-White 90mins), Davis, Keating, Koue Niate, Cameron, Andrews (Hall 87mins), Reid, Janneh, Lemonheigh-Evans, Kalala (Dickson 87mins). Subs not used: MacDonald, Hall, Williams.