The first came after eight minutes when Steven Bell tried to be too clever as he attempted to control the ball in the area and John Rankin pounced to send a low cross for Dargo to bundle the ball home.
It was 2-0 after 12 minutes. Roy McBain's cross was headed into the path of Dennis Wyness by Graham Bayne and he judged his left-foot volley to perfection to beat Myles Hogarth from 20 yards.
But Stirling pulled a goal back three minutes later when Chris Aitken fed David O'Brien and he beat Darren Dods for pace and clipped the ball past Mark Brown.
Caley Thistle came right back and went 3-1 up midway through the first half. McBain's net-bound shot struck Bayne but the ball broke back to him and he lashed a shot past Hogarth from the edge of the area.
But Stirling dug in and John Fraser saw a 25-yard shot beat Brown but crashed back off the crossbar.
Dargo made it 4-1 four minutes from the break when he took a pass from Wyness before chipping the ball over Hogarth from all of 30 yards for a glorious goal.
Barry Wilson then scored the fifth after 47 minutes when he drilled in a 25-yard shot after the Stirling defence backed off invitingly.
Bayne then hit a post as Stirling were overrun in midfield and it became a question of how many.
Hogarth will not have fond memories of the game and certainly not the sixth goal he conceded.
Substitute Alan Morgan had only been on the pitch for a couple of minutes when he beat the goalkeeper at his near-post with a shot from a seemingly impossible angle.