The odds-on favourite picked up his stablemate Shakespeare inside the final furlong to lead home a Ballydoyle one-two in the Criterium de Saint-Cloud.
Everything went to plan for Aidan O'Brien with Victory Speech taking the field along from Shakespeare at a decent early gallop. The last-named took over the lead and kicked for home off the final bend, but had no answer to the winner who had been smuggled into the race by Ryan Moore.
Jesus Green, who seemed to find the early gallop a little too frenetic, stayed on well to launch a challenge a furlong out but his effort petered out and he was eventually only third. The Godolphin runners - Royal Acclamation and Al Jabbar - were both well held.
The 9-10 favourite was delivering a seventh win in the race for O’Brien, but a first for Moore after wins for Soumillon aboard Pierre Bonnard 12 months ago and Los Angeles in 2023.
O'Brien, who was also winning the Group One contest for the third time in four years, said: "Ryan gave him a lovely ride, taught him plenty.
"He's a lovely horse. He handled the ground and got the trip well. I'm over the moon really – couldn't be happier.
"He could do either [French or British and Irish programme] but we will see what the spring brings."
Drumbeat's success took O'Brien to 24 Group One wins for the year, four short of matching his own 2017 record of 28.
Moore added: "He has a lot of quality, a very straightforward horse. He relaxed, found a good rhythm and when I put him in between horses in the straight, he really wanted it.
"He put his head down, went through the gap, picked up well. He's an exciting horse.
"There was plenty of room there and he had the pace to go take the gap and quicken up well. He's lovely, straightforward. He's a gentleman of a horse and plenty to look forward to."
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