Burning desire? (5)
I believe the answer is:
arson
'burning desire?' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for arson that I've seen before include "Crime involving fire" , "Crime of fire-setting (5)" , "Sonar (anag.)" , "matchplay, say?" , "Act of a pyromaniac" .)