System that stands for Marlow entering the heart of darkness (6)
I believe the answer is:
method
'system' is the definition.
(I've seen this before)
'stands for marlow entering the heart of darkness' is the wordplay.
I cannot really understand how this works, but
an anagram of 'the' is 'eth' which is present in the answer.
'of' could be 'o' and 'o' is present in the answer.
This explanation may well be incorrect...
'that' acts as a link.
Can you help me to learn more?
(Other definitions for method that I've seen before include "Fashion" , "'Means, way of achieving (6)'" , "Mode, procedure" , "System, perhaps even in madness" , "particular procedure" .)