Blackbeard led home stablemate The Antarctic to provide trainer Aidan O'Brien with a one-two in the Prix Robert Papin at Chantilly.
Unbeaten in his first three starts before finishing fourth when favourite for the Coventry at Royal Ascot, Blackbeard was last seen being beaten just a short head by Shartash in the Railway Stakes.
Turning out three weeks later, the No Nay Never colt was the 10/11 favourite to claim Group Two honours at the third attempt and ultimately did so in fine style in the hands of Ioritz Mendizabal.
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Having challenged Belbek for the lead from the off, Blackbeard asserted his authority inside the last of six furlongs to win comfortably.
His stablemate The Antarctic, who finished a close-up third in a Listed contest at Tipperary on his previous start, made late gains under Mickael Barzalona to finish best of the rest in second, three lengths adrift.
O'Brien was winning the Prix Robert Papin for only the second time, with his first victory provided by the Mick Kinane-ridden Rossini in 1999.
Mendizabal told Sky Sports Racing: "I won easy, very easy. He's a nice horse. Before and after the race he is not easy and next time I will speak with Ryan (Moore), but in the race he is easy.
"When we hit the front he went a little bit left but normally that is because they are a little bit babyish.
"It's incredible for me to ride for Aidan, amazing. My agent gets me the ride and then I speak with Aidan on the morning of the race.
"If Aidan wants to bring him back to France, I will be free every time."
Speaking at the Curragh, O'Brien said: "I was delighted with him. He's coming forward as he was a baby all along. Even though he was babyish today Ioritz, who rode him, was very impressed with him.
"He said he's gone very professional and won very easy. He's definitely progressing.
"We wanted to divide them up, with Little Big Bear coming here yesterday. He's right in the mix now for the Phoenix Stakes or the Prix Morny."
Of The Antarctic, he added: "We were very happy with him, he's coming as well. He's probably still not really there yet but he's definitely progressing."