Al Boum Photo gave trainer Willie Mullins his first victory in the Magners Cheltenham Gold Cup following a dramatic race for the showpiece event at the Prestbury Park course.
Leading at the second-last fence, Al Boum Photo (12-1) dug deep for jockey Paul Townend, who was also winning the Gold Cup for the first time.
Anibale Fly stayed on strongly to finish second, two and a half lengths away, with Bristol De Mai another three and three-quarter lengths back in third.
After six second places, Mullins finally broke his Gold Cup hoodoo. His three other runners - Kemboy, Bellshill and Invitation Only - failed to finish.
Mullins said: "I've got used to the disappointment of finishing second.
"I thought Bellshill would take a lot of beating, but Ruby (Walsh) wasn't happy with him and pulled him up early. To have three of the four runners out of the race before they came to the second-last first time round - I was depending on one.
"Every time I looked at Paul, his body language told me was very happy and the horse was relaxed.
"When he came over the last, I just looked at the winning post and thought nothing would come and get him unless he stops or runs out or something like that.
"I was here when my dad (Paddy Mullins) won with Dawn Run and I didn't get home for two days.
"I sort of resigned myself to never winning a Gold Cup. Certain jockeys may never win the feature race of their lives, like the Grand National or the Champion Hurdle. I thought maybe I'm not going to be lucky."
An emotional Townend - who hit the headlines for the wrong reason with Al Boum Photo at Punchestown last season, dramatically running out when in the lead - said: "I can't believe it. It's the Gold Cup, there's only one a year and I never dreamt I'd win it.
"Like any race, when you're going well it's so simple.
"It's unbelievable and I'm privileged to be riding for Willie Mullins."
It continues a winning streak for jockeys in Cork, with Jerry McGrath and Aidan Coleman also in the winner's enclusre this week.