Answer: collude

AnswerCrossword Clue
COLLUDEAct in unison
COLLUDECook up a scheme (with)
COLLUDEPlot
COLLUDEConspire
COLLUDECook up a plan (with)
COLLUDEPlan a heist (with)
COLLUDECabal
COLLUDEBe in cahoots
COLLUDEPlot (with)
colludeto act together through a secret understanding, esp. with evil or harmful intent
colludeto conspire (to plot together)
colludeto conspire in a fraud