The filly was dropping back to seven furlongs in the Group One contest under Ryan Moore, with her last outing being a fourth-placed run behind Inspiral in the Coronation Stakes over a mile at Royal Ascot.
For trainer Aidan O'Brien the three-year-old was triumphant for the first time since her Cheveley Park victory in 2021, prevailing by a length and a quarter from a field of 11 that included colts.
Moore had her settled off the early pace and there were plenty in with a chance coming into the final furlong, but when Moore gave the signal, Tenebrism found an extra gear to pull clear of a blanket finish for the places.
David Simcock's Light Infantry took second ahead of the Richard Hannon-trained Lusail in third. Charlie Appleby's French 2000 Guineas winner Modern Games was not beaten far in fifth.
"She's always shown us plenty, she won the Cheveley Park on her second start over six furlongs. She went to Newmarket for the Guineas and the ground was very firm that day, she got banged around, she never got into any sort of rhythm and didn't finish her race," Moore told Sky Sports Racing.
"She ran a good race at Ascot, she was still a little bit green and just struggled around the bend and then finished really well.
"It was nice to have her back on a level track on nice ground.
"She had to wait for a gap but as soon as she got a little bit of room, like a motorbike she powered straight through it.
"Caravaggio (sire) was very fast and she's out of Immortal Verse who won the (Jacques Le) Marois here in France. She's a pleasure to ride."