In the publicity the labyrinth caused a shock (6)
I believe the answer is:
amazed
'caused a shock' is the definition.
Although both the answer and definition are past participle verbs, I cannot see how they can define each other.
'in the publicity the labyrinth' is the wordplay.
'in the' means one lot of letters goes inside another.
'publicity' becomes 'ad' (short for advert).
'the labyrinth' becomes 'maze' ('maze' can be a synonym of 'labyrinth').
'ad' placed around 'maze' is 'AMAZED'.
Can you help me to learn more?
(Other definitions for amazed that I've seen before include "Awe-struck" , "Greatly surprised or astonished" , "Dumbfounded" , "Flabbergasted" , "Staggered" .)