Identity Thief took a step up to three miles in his stride to claim the Ryanair Stayers Hurdle at Aintree.
Henry de Bromhead's charge is a Grade One winner over two miles having landed the Fighting Fifth Hurdle at Newcastle back in 2015, and proved he retains plenty of ability when fourth in last month's Champion Hurdle at Cheltenham.
Having never raced beyond two and a half miles, the Gigginstown House Stud-owned eight-year-old was taking a step into the unknown on Merseyside, but saw out the extra distance comfortably to record a first victory since October 2016.
Coole Cody adopted a pacesetting role for much of the way before folding, allowing 6-5 favourite Sam Spinner to take the initiative rounding the home turn.
However, both Identity Thief and Wholestone picked him up fairly readily and it was the former who forged five lengths clear after the final flight in the hands of Sean Flanagan.
De Bromhead said: "I'm delighted. You dream, but I wasn't expecting that.
"You have to stay, but we just didn't know if he would or not. It was Sean's plan as he said he would love to go three miles. We said we would leave it to him how he wanted to ride him and fair play to Sean.
"We came here for the two-and-a-half (Aintree Hurdle) last year and we rode him positively and he was disappointing on the day.
"The way he ran in the Champion Hurdle, he stopped at halfway and ran on really well again at the end. We hoped the big step up would suit and it's fantastic.
"We will enjoy today, but we've always felt he is a good horse as he won the Fighting Fifth.
"He lost his form over fences but it is great to have him back and we will enjoy today. We've got him in the Stayers' Hurdle at Punchestown but we will see about that."
Ryanair and Gigginstown supremo Michael O'Leary was thrilled to win another race he sponsors, having finally broken his duck in the Ryanair Chase at Cheltenham last month with De Bromhead's Balko Des Flos.
He said: "It took me 15 years to win the first Ryanair, then I get two in the space of a month! They all come along together like buses. It's great."
Nigel Twiston-Davies, trainer of the runner-up Wholestone, said: "We've clearly got the best staying hurdler in Britain, but those pesky Irish keep coming and beating us!
"He's run another blinder. Whether he stays over hurdles or goes chasing (next season) will have to be discussed."
Jedd O'Keeffe said of Sam Spinner: "He's run another good race and has come an awful long way in a short period of time.
"It looked to me like he was a tired horse, though, so I think that will be it for the season.
"He definitely won't go to Punchestown and I don't think we'll go to France either. I suppose we'll have to school him over a fence at some stage, but Joe (Colliver) said he is still very babyish and is only six."