Having partnered Amberleigh House to glory in the Aintree showpiece back in 2004, the 39-year-old, who has also seen victory at the Cheltenham Festival, secured his maiden success at the highest level on the Flat since switching codes with a battling success aboard the Ed Dunlop-trained four-year-old.
Purchased for just 20,000 Guineas at a breeze-up sale in 2013, the son of Champs Elysees completed his rapid transformation through the handicap ranks, which included a win in the Chester Cup, to a genuine Group-class performer in the space of just six runs since this season.
Forever Now in the hands of Frankie Dettori took the field along through the early stages of the two-and-a-half-mile showpiece, with Vent De Force, Havana Beat and unbeaten favourite Forgotten Rules all positioned just in behind.
There was little change in the order until the home turn, where Dettori tried to steal a march on his rivals by kicking from the front.
With the early leader failing to draw clear of the field Forgotten Rules looked set to hand his trainer Dermot Weld a second win in the race having captured it with Rite Of Passage in 2010 as he forged into the lead hitting the two-furlong pole.
As the favourite made his move, Lee and Trip To Paris, who was supplemented at a cost of £35,000, were presented with clear daylight up the inside at the same time as the well-supported Kingfisher and Ryan Moore saw a gap close on them at a crucial stage.
Hitting the final furlong Forgotten Rules could offer no more as Trip To Paris surged past to take up a lead he was not to relinquish, coming home a length and a quarter to the good of the unlucky-in-running Kingfisher.
Lee said: “The second I got on him in the parade ring I knew he would run well because he was so relaxed and switched off. He went to post asleep and he kind of raced that way, he just had a dream run round.”
The victory for Newmarket handler Dunlop, who part-owns the horse, saw him follow in the footsteps of his father, John, who saddled Ragstone to victory in the 1974 renewal.
He said: “It’s amazing. My parents have the Gold Cup on the dining room table at home and it’s been there since 1974,” said the trainer.
“Credit goes to the owners. They bullied me into supplementing and it came off.
“His owners are all very sporting and put up with me – some have been with me since the start. There are seven of us in the partnership.
“He’s improved a lot. I brought him at the breeze-ups and he ran in the King George V Handicap last year with blinkers on.
“We suspected he might have the right temperament and turn of foot to be a stayer. His trial at Ripon showed that. I thought he was unlucky at Sandown when they went slow and sprinted.
“We gelded him and that was the making of him. He has a turn of foot for a stayer, he’s won over a mile and a half.
“He’s a very good horse now. He’s won a Chester Cup and a Gold Cup, which is a pretty big deal.
“Graham Lee has been a big part of this. I was bemoaning him going around the outside for a while, but he sensibly switched to the inside. It was a great ride.
“He has been phenomenal and is probably the most improved horse in training. This win ranks near the top of them and it is a dream come true.”
Having trained Red Cadeaux to finish second in three Melbourne Cups, Dunlop will give the ’race that stops a nation’ serious thought.
He said: “The Australians, the clever ones, said ’you don’t want to run in the Gold Cup, as it will ruin your handicap mark’, but I think the guys will want to do it now.
“He’s proven today he’s a very good horse and it will be considered.”
Kingfisher’s trainer Aidan O’Brien was magnanimous in defeat.
He said: “He ran a great race and we were delighted with the way he ran.”
Having made a late decision to run on the ground Weld refused to blame the conditions for the defeat of Forgotten Rules, with the master of Rosewell House feeling he did not quite see out the trip.
He said: “He ran a great race and I was satisfied with him. You win some, you lose some.
“It was a very close call, but I’m not blaming the ground. On the day we were beaten by two better horses.
“This was as far as he wants to go. He was the winner a furlong and a half down. I thought he didn’t quite get home. I’ve always said there’s a big difference from two miles to two and a half miles. He was cruising there after two miles.
“He is significantly better on soft ground, but all that said he’s run a big race. We will review the whole situation and take it from there.”
Simenon was fourth for the second year running, having filled the runner-up spot behind the Queen’s Estimate in 2013. Trainer Willie Mullins said: “It was great to come back for the third year in a row and get some prize-money and get into the winner’s circle.”