Embleton made eight changes from the opening day victory over Oldham. Dennis came in for his first appearance of the season along with McAnuff and Ruel Sotiriou, who both made an impact off the bench on Saturday. Dan Happe was left out as a precaution after suffering a knock at Boundary Park with Jamie Turley taking his place in the side.
It was another player brought into the starting eleven, Jordan Thomas, who had the first real effort of the tie. After breaking with the ball from deep, the full back on loan from Norwich played a nice one two with Sotiriou before curling a shot wide with his weaker foot.
Orient’s bright start continued moments later as Jordan Maguire-Drew worked his way into the box before seeing an effort deflected away for a corner.
Sotiriou was next to threaten, his low driven shot forcing Argyle keeper Mike Cooper into his first save of the game just a minute later.
Embleton’s side continued to create chances. In the 15th minute, Sotiriou pounced on a loose pass and laid the ball off to Maguire-Drew on the edge of the box, the winger then hit a fierce strike narrowly passed the post.
Two minutes later, the O’s had their best chance of a promising opening period. Dennis produced a teasing cross from the right which was parried into the path of Sotiriou, his goal bound effort was then innocuously blocked by Cooper with the Argyle keeper none the wiser regarding the stop.
Despite Orient’s encouraging start they found themselves behind in the 18th minute. Ryan Hardie created space for himself with some neat footwork eventually forcing Lawrence Vigouroux into a save from point blank range, but the Chilean couldn’t keep out the next effort from Panutche Camara who fired high into the roof of the net to open the scoring.
Buoyed by their opener, Argyle came again. Once more Hardie showed good feet to find space and rattled the woodwork with a rasping drive.
Sotiriou came close to levelling for the O’s but his stinging effort was smartly turned over by Cooper.
It was the visitors who were to grab the next goal however, a break away from an O’s corner saw Danny Mayor find space down the left, he then played a ball into the path of Kelland Watts who calmly slotted home to double his side’s lead.
Sotiriou remained the home side’s biggest threat, this time showing a rapid turn of pace to beat his man and get a shot off, though, much to the frustration of everyone in red, his effort cannoned back off the crossbar.
Ryan Lowe’s side had chances to put the game to bed before the break, but some tidy keeping from Vigouroux and the linesman’s flag denied them that opportunity, leaving the O’s two goals down at the interval and with it all to do.
Five minutes into the second half, Embleton elected to make his first switch of the evening, Josh Coulson making way for James Brophy in a reshuffle that saw Joe Widdowson move to centre back.
Dom Telford had a chance to add a third for Plymouth shortly afterwards but the forward failed to find the back of the net from a tight angle.
The Cypriot starlet, Sotiriou, picked up where he left off in the first half, turning his marker inside and out before seeing his cross turned behind for a corner. Orient did well to keep Maguire-Drew’s set piece alive and the ball eventually fell to the former Brighton man whose cross was met on the volley by Dennis to put the O’s right back in the tie.
That strike proved to be Dennis’ last action on the pitch as he was replaced by James Dayton, a solid first hour of football this season for the former Portsmouth man.
Orient pressed for an equaliser with a couple of half chances but they were almost dealt a sucker punch on the counter with only an acrobatic save from Vigouroux denying Cooper a third for the Pilgrims.
Embleton’s men then found a deserved equaliser. McAnuff was played in behind the Argyle defence and showed a ridiculous amount of composure and class to dink the ball over Cooper and into the net to level the scores in the 74th minute.
Dazzling footwork from Maguire-Drew almost put the O’s ahead in the 82nd minute. The Argyle defence eventually cleared his dinked effort out of the box and into the path of Josh Wright who hit an audacious volley just wide of the mark.
Orient weren’t done there though; the turnaround was complete in the 90th minute and once again it was that man Danny Johnson. The forward, who had replaced Lee Angol in the aftermath of the equaliser, pounced on a mistake in the Argyle backline and calmly slotted passed Cooper to send the O’s players and coaching staff into bedlam.
Moments later, referee Joshua Smith blew the final whistle to seal Orient’s place in the third round and setup a mouth-watering tie against Josè Mourinho’s Tottenham Hotspur.
ORIENT: Vigouroux, Widdowson, Coulson (Brophy 51”), McAnuff, Maguire-Drew, Thomas, Dennis (Dayton 62”), Angol (Johnson 74”), Sotiriou, Turley, Wright
SUBS: Sargeant, Ling, Cissé, Ogie
GOALS: Dennis 55”, McAnuff 74”, Johnson 90”
PLYMOUTH: Cooper, Watts, Aimson, Wooton, Hardie, Mayor, Telford (Nouble 66”) MacLeod (Grant 84”), Moore, Camara, Cooper (Edwards 74”)
SUBS: Ruddy, Canavan, Lolos, Pursall
GOALS: Camara 19”, Watts 34”
REF: Joshua Smith