While glory in the Group One contest was a first for Hannon, his filly succeeded by just a neck in denying Brian Meehan his third consecutive win in the race as his Dhanyata was agonisingly outbattled and had to settle for second.
The race was stripped of its biggest name when Stan James 1000 Guineas favourite Sander Camillo was ruled out due to the softening ground, but her absence failed to detract from a pulsating renewal.
Scarlet Runner and La Presse duelled up front for most of the six-furlong race, with Richard Hughes content to sit in just behind on the 3-1 joint-favourite.
He then sent Indian Ink about her business two furlongs out, although her every stride was matched by Jimmy Fortune on Dhanyata.
The latter struck her nose in front inside the distance, but Indian Ink revelled in the ground and stayed on best of all to take the £96,526 first prize, adding to the £136,570 she picked up at Ascot seven days ago.
Meehan, who has struck in the past two runnings with Magical Romance and Donna Blini, came close to completing a clean sweep with Dhanyata, and she was followed home by Silca Chiave under Ted Durcan.
French raider Magic America was the other joint market leader but the Prix Morny second was always in rear and finished sixth, failing to add to his trainer Criquette Head-Maarek’s three previous wins in the race.
Indian Ink had been at home in testing conditions at Ascot, and Hannon said: “I was delighted to see the rain.
“She got into trouble going into the Dip but when she hit the rising ground she ran on again – I did think we were in bother for a second.
“We went for the money in the Watership Down race but she won that easily and we decided if she came out of that race well she would come here if they got the rain – which they did, and here we are.
“That’s it for her this year. She’s had five quick races.”
Peter Chapple-Hyam enjoyed his first domestic Group One victory since returning from Hong Kong in the spring of 2004 when Dutch Art powered to success in the Shadwell Middle Park Stakes.
Dettori’s mount bounced out of the stalls and pulled hard through the early stages as he jostled for the lead with Brave Tin Soldier and Captain Marvelous.
But once the Italian asked the Paul and Susan Roy-owned Dutch Art to quicken the response was immediate and the juvenile powered clear with an electric turn of foot to score by an easy two lengths.
Wi Dud came from off the pace to take second, with the outsider of the field Captain Marvelous (33-1) a length and a quarter back in third.