Joshua King scored a hat-trick against his former club as Watford beat Everton 5-2 to end a run of three matches without victory.
Everton's Tom Davies opened the scoring after only three minutes, sliding in to convert Demarai Gray's cross at the near post.
King levelled from close range 10 minutes later.
Richarlison restored Everton's lead three minutes after coming on as a second-half substitute.
But Watford struck four times in the remaining 12 minutes of the match. Juraj Kucka headed the first from a corner before King added his second.
The Norwegian then finished low past Jordan Pickford to claim his hat-trick before Emmanuel Dennis completed the scoring in the first minute of stoppage time.
Claudio Ranieri's first win as Watford manager leaves them 14th with 10 points. Everton stay eighth with 14 points.
See: Everton report | Watford report
Next fixtures
Everton: 1 Nov v Wolves (A)
Watford: 30 Oct v Southampton (H)
Match officials
Referee: Graham Scott. Assistants: Marc Perry, Timothy Wood. Fourth official: Jonathan Moss. VAR: Martin Atkinson. Assistant VAR: Lee Betts.
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