The pre-match hype had surrounded the selection of England youngsters Matthew Tait, Toby Flood and James Haskell in the starting XV, but it was the 21-year-old Welshman who stole the show.
With only three minutes on the clock Hook charged down Flood's attempted clearance and then added to his try with his first conversion.
While Flood looked shaky at no.10 for England, Hook revelled in the occasion and showed a maturity beyond his years with a spectacular penalty kick 44metres out.
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Gareth Thomas and Gethin Jenkins linked up well, before Chris Horsman drove over the England line to give Wales a magnanimous 15-0 lead.
But England managed to haul their way back into the game, through captain Mike Catt and scrum-half Harry Ellis.
First 35-year-old Catt sliced the Welsh line apart with a dummy and while it looked like he would over run his own kick, the ball took a fortunate bounce and Ellis followed up to grab an England try.
The scorer then turned provider as Ellis steamed ahead and looped a long pass to the only other man quick enough to keep up, Jason Robinson.
After a scintillating first half the score was level at 18-18, but in the second there wasn't a try in sight and it was only the boot of Hook that made its way onto the scoreboard.
England were hampered by the loss of Catt - only two minutes into the second half - after he tweaked the hamstring that had been hindering him all week.
Two penalty kicks and a drop goal in the 68th minute were enough to see the Welsh secure victory over the old enemy.
The world champions, who needed an improbable 57-point victory to deny France the title, were second-best all day and have to settle for third place on six points behind Ireland and the French.
"In the first 20 minutes we were almost blown away but I thought the players showed a lot of resilience to get back into it," said England coach Brian Ashton.
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