Wasps ended Bath’s 15-month unbeaten home record in the Guinness Premiership with an extraordinary second-half performance at the Recreation Ground.
The visitors, needing a win of any sort to preserve their hopes of reaching the play-offs, ran in five tries to claim a bonus-point win as Danny Cipriani top scored with 22 points.
Bath saw a 20-13 half-time lead obliterated as Wasps ran up 22 points without reply, but the home side also scored four tries to claim a bonus point.
All went smoothly early on for the hosts as Olly Barkley kicked things off with a second-minute penalty.
He was also closely involved in the opening try, setting Andrew Higgins free on a 40-metre run that eventually saw the winger score under the posts.
The conversion was a simple affair for Barkley and Bath led 10-0 after only five minutes.
Wasps quickly hit back with a Cipriani penalty and five minutes later the England starlet fashioned a virtuoso try.
He launched a deft chip over the blindside defence and collected the ball himself before running 40 metres to score and then added the conversion.
Pegged back to 10-10, Bath put in some big tackles as a sign of their intent and Barkley was wide with a 40-metre penalty.
Both sides were being warned about infringements at the breakdown as Bath stepped up their intensity.
Fly-half Shaun Berne slipped past the tackles of Cipriani and Joe Worsley only to drop the ball over the line, but when Wasps infringed again Barkley chipped over a short-range penalty.
That was cancelled out by a 40-metre effort from Cipriani on the half hour but he then missed a long-range penalty that would have given Wasps the lead.
Instead it was Bath who stretched ahead on the stroke of half-time when full-back Nick Abendanon scrambled over to the satisfaction of the TV match official and Barkley converted to put his side 20-13 in front.
However, that was the last they saw of the ball for a good while as Wasps grabbed the initiative after the break.
First England back row James Haskell strolled in under the posts for a try converted by Cipriani, and the Bath defence went walkabout again when David Doherty created the extra man for Josh Lewsey to score.
Cipriani could not convert but knocked over a penalty to take Wasps two scores ahead after 15 minutes of the half.
Bath coach Steve Meehan made several changes off the bench but it made little difference and Lewsey again found space to score his second try, and with Cipriani’s conversion the visitors’ lead was suddenly 15 points and Bath looked shell-shocked.
But they clawed their way back into contention when Eliota Fuimaono-Sapolu finished off a move sparked by fellow replacement Jonny Faamatuainu.
Barkley converted but Wasps took the affair beyond doubt when Dan Leo forced his way over at the other end, Cipriani converting.
There was a final fourth try for Bath, scored by Daniel Browne, but the hosts were a beaten side.