Gillingham deservedly produced a huge FA Cup shock with victory over the Premiership's form team Charlton.
They had to overcome conceding a goal after just 34 seconds when defender Ian Cox turned the ball into his own net.
But Tommy Johnson levelled with a low drive and two minutes later, Mamady Sidibe's header put the Gills ahead.
They sealed the win when Paul Smith rifled a shot low into the right bottom corner, before Carlton Cole responded.
The result could have been even more comprehensive as Gillingham took full advantage of a Charlton side clearly missing the influential Scott Parker.
But as they headed towards their giantkilling they had young French goalkeeper Bertrand Bossu to thank for preventing a more tense finish.
His spectacular triple save with just over five minutes to go belied a nervy performance and virtually guaranteed Gillingham progress.
When Charlton finally did break through, it came to late too rescue them.
1 min: Charlton take the lead through Cox's own goal
17 mins: Johnson's low drive puts Gillingham level
19 mins: Sidibe heads Gillingham in front
34 mins: Gillingham go further ahead through Smith
90 mins: Cole pulls one back for Charlton
Cole, on loan from Chelsea, tapped in after another good save from Bossu.
It had all started so differently, when Bossu flapped at Paul Konchesky's cross and a confused Cox turned the ball into his own net.
The signs looked ominous for the First Division side as Charlton then spent the next 10 minutes carving out chances at will.
But up stepped Johnson to begin the comeback for the hosts, and ultimately turn the game on its head.
He shook off the challenge of Hermann Hreidarsson and drove a low shot which beat Dean Kiely at his near post.
The Charlton keeper would have been disappointed, but there was worse to come.
After a lovely one-two with Sidibe, John Hills found space on the left and crossed dangerously.
It was only half-cleared by Hreidarsson and the ball fell invitingly to the oncoming Smith.
He had plenty of time to tee up his shot, but despite a good connection, it again appeared that Kiely could have done better.
And the ball nestled in the bottom right corner to send Gillingham two goals clear.
Before that Mali international striker Sidibe had powered a header past the despairing Kiely to give Gillingham the lead for the first time.
The introduction of Paolo di Canio just 11 minutes into the second half did not have the impact Charlton were looking for, although the Italian did hit the post in the 79th minute.
However, before then, Sidibe, Smith and Johnson all had chances to increase Gillingham's lead as they continued to boss the match.
But three goals proved enough to send Gillingham into the fourth round for the fourth successive year.
Gillingham: Bossu, Nosworthy, Cox, Hope, Hills, Southall,
Smith, Spiller, Shaw, Tommy Johnson (Henderson 75), Sidibe.
Subs Not Used: Leon Johnson, Rose, Jarvis, Awuah.
Charlton: Kiely, Kishishev (Euell 64), Fortune,
Perry (Di Canio 57), Hreidarsson, Stuart, Holland, Jensen,
Konchesky, Johansson, Cole.
Subs Not Used: Fish, Royce, Hughes.
Referee: J Winter (Cleveland).