Watford produced one of the great FA Cup comebacks by coming from two goals down to beat Wolverhampton Wanderers 3-2 after extra time of a memorable semi-final at Wembley Stadium.
Two-goal substitute Gerard Deulofeu proved Watford's hero as they reached the FA Cup final for the first time in 35 years in astonishing fashion.
The Spaniard scored a sensational individual goal to drag his side back into the match when they were 2-0 down with 11 minutes left and then slotted home the winner in the opening period of extra time.
Striker Troy Deeney also enhanced his folk hero status at Watford by nervelessly converting a penalty with the final kick of stoppage time in the 94th minute to enable the Hornets to take the game into extra time.
A first-half header from Matt Doherty and a dazzling piece of skill which saw Mexican Raul Jimenez chest down and volley home acrobatically just after the hour had looked set to be enough for Wolves to prevail in the all-Premier League clash.
Yet an equally virtuoso 79th-minute goal from Deulofeu - a magnificently executed curling chip - set up the amazing finale which saw Deeney blast home from the spot after being brought down by Leander Dendoncker.
Spanish international Deulofeu then delivered the killer blow a minute before the break of extra time, driving past Conor Coady on the right before slipping the ball across John Ruddy and into the net.
It earned Watford a date with overwhelming favourites Manchester City, who beat Brighton & Hove Albion 1-0 in Saturday's other semi-final, in the final back at Wembley on May 18.
It also gave them the chance to play in only their second FA Cup final, after losing to Everton in 1984.
Watford captain Deeney told BT Sport after the match: "All I wanted was a decent cross, I'd been chasing it all day. Thankfully I got there before him (Dendoncker) and it's a clear penalty.
"I'm not going to lie, I just hit it as hard as I could. You know if you miss you're out so I just had a word with myself and calmed down.
"I'd been practising them but this emotion you can't really create on the training pitch so I took myself away and calmed myself down and got myself in that training pitch mode."
Deeney added: "I've said on many occasions that this team has something special. We're not the most talented, we're not all that, but the hard work and desire at 2-0 down - many teams would've called it a day but we kept fighting and kept going and brought the little man on, who produced a bit of magic.
"We've got room to grow, there's not a ceiling on us yet a a team. For a club of this size, let's enjoy this moment.
"Manchester City are a formidable team, probably the best team in Europe, but it's a one-off game and we need to come in with belief and know that this hard work can get us a long way."