Farclas opened his account over jumps with a gritty performance to land the JCB Triumph Hurdle at Cheltenham.
Second in both his previous starts, the grey gelding made it third time lucky as he gave trainer Gordon Elliott a seventh winner at the meeting and jockey Jack Kennedy a fourth in the ever-familiar colours of Gigginstown House Stud, who have also had a successful time this week.
Stormy Ireland made most of the running, but she was under pressure when falling at the final flight, as several horses had every chance.
Farclas (9-1) stuck his head in front and kept up the momentum to hold Mr Adjudicator at bay by a length and three-quarters. The latter's trainer, Willie Mullins, was also responsible for the third, Sayo, who was three and a half lengths away.
Apple's Shakira, the Nicky Henderson-trained 6-5 favourite, was only fourth.
Kennedy said of the winner: "He's been running very well in his last two races and improving all the time. Gordon had him spot on today.
"He (Elliott) has done so well with these horses - it's unreal. He just leaves no stone unturned, his attention to detail is second to none."
Elliott said: "It's great, we're having an unbelievable week. I keep saying to the staff and owners that it's unbelievable, and it's a big thanks to everyone.
"On his first run he was beaten in a Grade Two, then he was beaten in a Grade One by the second (Mr Adjudicator), so there was only a good jump between them and the Irish form stood up."
Gigginstown boss Michael O'Leary said: "I was very surprised as I didn't think the fillies (Apple's Shakira and Stormy Ireland) would be beaten today, but they both pulled very badly all the way round.
"He's only run twice and been beaten twice, so it's one of those nice days where if he hadn't have won, we'd have kept him a novice for next year, but we're very, very happy to win the Triumph with him.
"He settled and he's getting stronger and stronger. Gordon has always loved him."
Henderson of Apple's Shakira, who was losing her perfect record at Cheltenham: "She was far too keen.
"We will put a hood on her and aim her for Aintree now."