Bath (20) 34
Try: Higgins, Abendanon, Fuimaono-Sapolu, Brown
Pens: Barkley (2)
Cons: Barkley (4)
Wasps (13) 42
Try: Cipriani, Haskell, Lewsey (2), Leo
Pens: Cipriani (3)
Cons: Cipriani (4)
Bath's 100% home record was shot to pieces by a superb second-half display by Wasps, who ran in five tries.
Andrew Higgins and Danny Cipriani traded tries in a lively opening period but the only other try of the half was right at the end, from Nick Abendanon.
Wasps struck back after the break, with tries by James Haskell and Josh Lewsey (2) turning the match on its head.
Eliota Fuimaono-Sapolu gave Bath hope before Daniel Leo's try sealed it, but Daniel Brown earned Bath a bonus point.
Higgins notched the opening try for Bath in bizarre fashion, bursting through from deep inside his own half, only to seemingly run out of steam within yards of the Wasps line.
606: DEBATE
But his stray off-load was knocked back to him by a Wasps hand, allowing him to canter in and score.
But Cipriani soon restored parity, getting on the end of his own chip forward and leaving Abendanon flailing at fresh air as he ran in to touch down.
Kickers Cipriani and Olly Barkley continued to match one another point for point but the Wasps player wasted a great chance to put his side ahead just before the break when he put a relatively straight-forward kick wide.
And Bath made Wasps pay, Barkley's long kick caused confusion between Lewsey and Mark van Gisbergen, causing him to knock on.
From the resulting scrum, Abendanon made amends for his missed tackle in the build-up to Wasps' try as he slipped through several challenges to slap the ball down for a try.
Two tries in the first nine minutes after the restart put Wasps ahead, the first coming when Haskell went over after a fine forward move, and the second being finished off in the corner by Lewsey.
This set the home side reeling, and sensing that their opponents were stunned, Wasps tried the same approach again, with Lewsey bagging his second of the day.
Fuimaono-Sapolu's try gave Bath hope, only for Leo's pushover to settle any Wasps nerves.
Replacement Brown scored for the home side to earn a bonus point and round off a remarkable afternoon at the Rec, but Wasps took all the glory.
"It was almost inconceivable. Defence has been one of our strengths over the last 12 months.
"Our indiscipline gave them their chances in the first half so we had to make sure that it didn't happen again.
"But in the first 20 minutes of the second half we just didn't get our organisation right. I'm not sure why."
"The 20 minutes after half-time was as well as we've played this season.
"We've had catching up to do after the World Cup. We've got to play that well every week."
Bath: Abendanon, Maddock, Crockett, Barkley, Higgins, Berne, Claassens, Barnes, Mears, Stevens, Short, Grewcock, Beattie, Lipman, Feau'nati. Replacements: Dixon, Jarvis, Browne, Faamatuainu, Baxter, Fuimaono-Sapolu, Banahan
Wasps: Lewsey, Hoadley, Waters, Waldouck, Doherty, Cipriani, McMillan, Payne, Ward, Vickery, Shaw, Palmer, Haskell, Worsley, Hart. Replacements: Buckland, Adams, Leo, Webber, Reddan, Walder, van Gisbergen.
Referee: Rob Debney (Leicestershire)
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