Also involved a red revolutionary in the trials (7)
I believe the answer is:
ordeals
'trials' is the definition.
(I've seen this in another clue)
'also involved a red revolutionary in' is the wordplay.
'involved' indicates anagramming the letters (involved can mean confusing or complex).
'revolutionary' is an anagram indicator.
'in' means one lot of letters goes inside another.
'red' with letters rearranged gives 'rde'.
'also' with letters rearranged gives 'oals'.
'oals' going around 'rde' is 'ORDEALS'.
'the' is the link.
(Other definitions for ordeals that I've seen before include "Testing experiences" , "difficult tests" , "Difficult experiences, hard times" , "Tribulations" , "Trying experiences" .)