Louis Saha celebrated his new contract with a stunning double to sink Barclays Premier League leaders Chelsea tonight.
The Frenchman, who signed a two-year deal last week, first exposed Chelsea's weakness at set-pieces with a headed equaliser and then fired a brilliant 75th-minute winner at Goodison Park.
Chelsea had shaded the early stages and taken the lead through Florent Malouda but Saha, who also missed a penalty, secured Everton's first victory over the Londoners since 2000.
With Manchester United held by Aston Villa, victory could have taken Chelsea four points clear at the top but Everton's greater industry merited victory.
Sacked England captain John Terry escaped lightly in terms of crowd abuse following recent media revelations but the Chelsea stalwart was caught out for Saha's winner.
And of further concern for manager Carlo Ancelotti was the nature of the equaliser - the 16th of 22 goals this season Chelsea have conceded from set-pieces.
Everton scored all their goals from similar situations when the sides played out an entertaining 3-3 draw at Stamford Bridge two months ago.
This time the Toffees were without key midfielders Marouane Fellaini and Steven Pienaar through injury and suspension respectively.
Mikel Arteta, having recovered from a knee injury, made his first start in almost a year while Chelsea replaced Michael Ballack with Yury Zhirkov.
Everton stretched Chelsea within the opening minutes as Landon Donovan broke clear but the American overhit his cross for Saha.
After that Chelsea began to take control with Frank Lampard shooting wide after a Nicolas Anelka dummy and Didier Drogba heading over from a Malouda cross.
Branislav Ivanovic then volleyed wide but Chelsea broke through after 17 minutes from a route-one ball.
Peter Cech's long clearance was headed on by Drogba and Malouda brushed off the challenge of Phil Neville to drill a left-footed shot low past Tim Howard.
Chelsea threatened again when Richardo Carvalho leapt above Terry to meet a Lampard corner but Howard saved comfortably.
Everton then launched a counter-attack with Diniyar Bilyaletdinov breaking down the left to cross for Leighton Baines but the left-back caught his volley awkwardly and Cech saved.
But the Toffees grew in confidence and pulled level after winning a corner in the 33rd minute.
Donovan's cross dropped over Lampard and Saha rushed in to power a header past Cech for his 12th goal of the season and his first in five games.
Everton almost added an immediate second as Tim Cahill set up Leon Osman on the edge of the area but his shot flew wide.
Drogba pulled the ball back from the byline as Chelsea responded but Anelka stabbed wide from six yards.
Lampard tried his luck from a 30-yard free-kick but shot over and Drogba then curled one wide.
But Everton finished the half with a flourish and Saha should twice have given the hosts the lead.
First he was picked out in front of goal by Donovan but his first touch bought Cech time and the keeper rushed forward to save from point-blank range.
The former Manchester United forward had an immediate chance to make amends after Donovan was felled in the area by Carvalho but Cech guessed right and saved the resulting spot-kick to his left.
Everton did not let the miss affect them and started the second half well with a dangerous Bilyaletdinov cross palmed over the bar by Cech.
Saha then showed brilliant control to turn and create another shooting opportunity in the box but Carvalho just did enough to force him to fire wide.
Everton also started winning the 50-50 balls and Drogba showed a growing Chelsea frustration when he fired wildly at goal from more than 40 yards.
Bilyaletdinov showed good control in the area but his shot was blocked and a Donovan cross was just too high for Cahill.
Everton appealed for handball against Terry on the edge of the area but referee Alan Wiley's decision to play on was vindicated as replays showed the ball catching the face.
Pressure finally paid off as Everton deservedly went ahead through Saha after 75 minutes.
Terry missed the chance to cut out a long ball from Sylvain Distin and Saha brilliantly chested the ball down before turning and firing home powerfully with his left foot.
Chelsea, having been subdued for most of the second half, finally sparked into life but the crossbar came to Everton's rescue as Drogba met a Lampard corner with a good header.
Lampard then got in a shot at the end of a flowing move but Howard saved to his right.