After Blackpool's most efficient half of the season, Lee Clark's side capitulated in the second 45 minutes at Vicarage Road, finishing on the wrong end of a Watford mauling.
The visitors had frustrated their hosts before the interval, and were good value for their lead which came courtesy of Andrea Orlandi and Steven Davies.
However The Hornets flipped the scoreline in the space of nine minutes, before running riot over the visitors.
Odion Ighalo helped himself to four, while Troy Deeney, Matej Vydra and Gabriele Angella punished the visitors further.
Going against the league table it was The Seasiders that settled the quickest, and after a number of crosses into the box Ishmael Miller dragged the first shot of the contest wide, before Angella crashed a header over for Watford.
However Blackpool built on their positive start and stunned their hosts by edging ahead on eight minutes. Jamie O'Hara's ball created confusion between Heurelho Gomes and his defender, allowing Orlandi to pounce on the loose ball and lash Pool ahead.
The unforeseen start kicked Watford into life, and Deeney combined with Vydra, who shot wide of Ell Parish's net. The goalkeeper was being kept busy, with Ikechi Anya stinging his palms on 21 minutes.
Blackpool were successfully foiling their hosts during the first half an hour, with Miguel Layun blazing over and Ighalo seeing his effort palmed away by Parish.
The visitors finished the half the stronger side however, with Miller forcing a corner out of Gomes. And indirectly from that set piece Pool doubled their lead, Tony McMahon did brilliantly to turn his man and fire a cross towards Davies, who shot home at the second attempt from close range.
The Seasiders ended their most efficient half of the season on the front and Miller's saved shot was the final action of the half.
Half Time: Watford 0 Blackpool 2
However for all their good work, Watford came out for the second half a different animal and went about turning the contest on its head. Miguel Layun helped start the revival by springing Blackpool's offside trap before squaring for Ighalo to tap home their first.
And after Deeney had shot wide the hosts levelled through their captain. The striker met Daniel Tozser corner and glanced home the equaliser past Parish.
Blackpool had now fallen apart, and on 54 minutes, just nine after the restart, the turnaround was complete as Ighalo broke free and slotted underneath Parish to send Vicarage Road wild.
Injured in attempting to stop the third goal, Peter Clarke was then forced off through injury, with Niall Maher coming on for his debut, but that did nothing to close the floodgates.
Vydra was next to get amongst Watford's scorers, firing home after a clearance fell to his feet.
Blackpool's were shell shocked, and Jamie O'Hara's free-kick, which was well saved by Gomes, failed to reduced the deficit, instead Watford further increased their lead soon after.
Following a corner Angella pounced on the rebound to tap home their fifth, and it would have been six had Parish not saved from Ighalo at close range.
Nathan Delfouneso then replaced David Perkins, but Watford simply added a sixth. A demoralised Blackpool watched Deeney hit the post, before the ball cannoned off Ighalo for the striker's hat-trick.
And it didn't take the striker long to continue the embarrassment, after McMahon was robbed of possession Deeney rounded Parish before teeing up Ighalo to tap home.
Islam Feruz then replaced Davies, but the game petered out from that point and Blackpool were well beaten.
Full Time: Watford 7 Blackpool 2