Having looked a smart prospect when disposing of Kew Gardens easily in the Lingfield Derby Trial, he subsequently came up short at Epsom in the Derby and then in the Irish equivalent.
Given a mid-season break and ridden by Oisin Murphy for the first time, he was left alone at the head of affairs and held a clear five-length advantage with two furlongs to run, never looking likely to be caught.
French Derby winner Study Of Man was one of the first to be pushed along by Stephane Pasquier and while he did eventually run on into third, it was an underwhelming return to action from the colt, who has the Irish Champion Stakes as his big aim.
Patascoy was the only one to make any inroads into Knight To Behold's advantage, but the winner came home four lengths clear.
For Dunlop, it was just a relief to get his colt back on the right track.
"We're so pleased because he's a horse we've always thought the world of and while the Derby was a nice dream, it obviously went very wrong," he said.
"Then after the Irish Derby it was pretty clear that he wasn't staying a mile and a half in that company, so we wanted to bring him back to 10 furlongs and Mr (Neil) Jones (owner) was keen to keep him against three-year-olds.
"That meant taking on the French Derby winner, but we were able to just let him roll along in front - I put cheekpieces on just to help him concentrate.
"It looks like we've got back the horse we always felt he was, he was impressive.
"I think we'll keep him at 10 furlongs for now, but he's got no fancy entries as we didn't know where we were going with him.
"Most of the big races are now closed, so I'll talk to Mr Jones. It might be the Prix Dollar or something, but it's just nice to get him back on track."
The two other Group races on the card went the way of Andre Fabre with Wind Chimes winning the Prix de Lieurey in clear-cut fashion while Talismanic returned to action after a break with an easy win in the Prix Gontaut-Biron.
Having won the Breeders' Cup Turf last year, Talismanic ran in the Dubai World Cup on dirt but he failed to handle the surface. Back in lesser company, he dominated the field under Mickael Barzalona.
Chris Wall's First Sitting, who won the race 12 months ago, stuck on in determined fashion for third, just behind Subway Dancer.
Godolphin's Lisa-Jane Graffard said: "It was brilliant to see Talismanic win today. He is still as happy as ever to be racing.
"He came into today's race off of a long break and is a horse who needs a bit of readying for his races. He is very laid back and has such a great temperament.
"Depending on how he comes out of today's race, Mr Fabre is looking now at the Prix Foy (September 16) followed by the Prix de l'Arc de Triomphe," she told http://www.godolphin.com.