When Marshall tried to repeat his earlier pass three minutes before the break, Hawke's Bay-born Harris was alert to the danger.
Playing in front of his family sitting in the aptly-named Harris Stand, he intercepted the pass to send a flying Marika Koroibete, who had been denied earlier in the half, away on an 80m dash to the line.
The 12-0 halftime deficit was perhaps a little harsh on the Dragons who had matched their pre-game talk of an improved defensive effort in the Storm's opening set.
Matt Duffie defused a testing bomb for his first touch in a Storm jersey in 847 days before almost being driven back in-goal. The Red V kept up the intensity to force Cronk to kick from inside his own 20m.
They were again to the fore soon after the interval with five tacklers combining to thwart a hard-charging Kevin Proctor from extending the Storm lead.
But they struggled to get anything going on attack and seconds after a chant of "Melbourne, Melbourne" rang out Proctor latched onto a short ball from Cronk to extend the 'home' side's lead 15 minutes after the resumption.
Harris, who designed the one-off jersey worn by the Storm, then had his second assist of the night to retrieve a knockdown from a Cronk bomb and send Mahe Fonua over in the corner to put them up 22-0 and the result beyond doubt.
They still had enough time to have tries to Blake Green and a second to Fonua ruled out for forward passes as the fire went out of the Dragons before they claimed a late consolation to centre Peter Mata'utia.
Storm captain Cameron Smith said the intensity shown by the Dragons early on did not come as a surprise.
"It felt like they were playing for their season tonight, they've been going through a fairly rough patch," Smith said.
"You can tell with their energy and their defence they were here to get two points.
"We took a lot of punishment early and we had to do some pretty hard work, particularly off our own tryline and we held them out for 75 minutes of the game."
Dragons coach Paul McGregor said the Storm did more with the ball than they managed.
"Melbourne gave us a good lesson on how to build pressure," he said.
"I thought our defence was really solid.
"We're not building any pressure with the ball - far too many passes hit the deck."
- AAP