Trick the sick with due deviousness (6)
I believe the answer is:
illude
'trick' is the definition.
(I've seen this before)
'sick with due deviousness' is the wordplay.
I cannot quite understand how this works, but
'sick' could be 'ill' (synonyms) and 'ill' is located in the answer.
an anagram of 'due' is 'ude' which is within the answer.
No letters remain.
This explanation may well be incorrect...
'the' is the link.
Can you help me to learn more?
(Another definition for illude that I've seen is " Trick".)