A five-star display from striker Alex Battle ensured that Argyle maintained top spot in the Football League Youth Alliance Southern Section.
Battle grabbed a hat-trick plus an assist for Jason Vincent as the Pilgrims beat a useful Exeter side at Elburton Villa's Haye Road ground.
It was the Grecians who began the game in the ascendancy, taking a 10th minute lead after goalkeeper Michael Cooper had been penalised for handling a back-pass.
The impressive Frank Rosenwald slid the free-kick sideways to Archie Collins who blasted a low drive past Cooper from 10 yards.
Cooper made amends two minutes later with a fine one-handed save to keep out Rosenwald's first time drive, and that was the signal for Argyle to gain a foothold in the game.
Their equaliser finally arrived on the half hour when Battle hit a rasping, first time, drive from the angle of the visitors area that goalkeeper Kavanagh Keadell could only help into the far top corner of his goal.
Argyle were in the lead, three minutes later, when great play from Battle, wide on the right, saw his excellent cross find Jason Vincent heading home his 10th goal of the season.
City came back at Argyle and only a goal-line clearance by Aaron Taylor prevented Toby Down's header finding the back of the net.
The home side started the second half well and a great move between Dan Rooney and Battle ended with Alex Fletcher scooping the latter's cross over the visitors' bar.
Argyle's forceful running saw them deservedly notch a third goal, on 65 minutes, when Fletcher's strong run through the middle ended with him slipping the ball to Battle who struck a low drive across Keadell and inside the far post.
Battle and substitute Luke Jephcott combined to set up Vincent to fire over the bar before Argyle completed the scoring, six minutes from time, as Vincent won possession outside the box before finding Battle, who supplied the perfect finish from just inside the area.
Argyle: Michael Cooper, Billy Palfrey, Jamil Roberts, Aaron Taylor, Jordan Bentley, Liam Knowles, Jason Vincent, Jack Calver, Alex Fletcher (Cameron Sangster 77) Dan Rooney, Alex Battle. Substitutes not used: Harry Downing, Harry Hodges, Max Childs.