Sneaky scheme (4)
I believe the answer is:
ruse
'sneaky scheme' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ruse that I've seen before include "Subterfuge" , "Sure to be a trick" , "Plan intended to deceive" , "Trick designed to deceive" , "Cunning plan" .)