Answer:

switcheroo

AnswerCrossword Clue
SWITCHEROOSurprising variation
SWITCHEROOUnexpected reversal, in slang
SWITCHEROOCounterscam
SWITCHEROOSudden reversal
SWITCHEROOUnderhanded change, slangily
SWITCHEROOSlangy reversal
SWITCHEROOTricky swap