Trick, ruse (8)
I believe the answer is:
artifice
I believe this clue is a double definition.
'trick' is the first definition.
(I've seen this before)
'ruse' is the second definition.
(synonyms)
(Other definitions for artifice that I've seen before include "Trick, device" , "Clever trick, crafty ploy" , "Crafty trick - if I react (anag)" , "Capital of Tuvalu" , "Subtle deception" .)