A dramatic reminder (8)
I believe the answer is:
prompter
'a dramatic reminder' is the definition.
'prompter' can be an answer for 'reminder' (I've seen this before). I am not sure about the 'a dramatic' bit.
'reminder' is the wordplay.
I cannot quite see how this works, but
'reminder' could be 'prompt' (I've seen this before) and 'prompt' is present in the answer.
The remaining letters 'er' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for prompter that I've seen before include "Supplier of lines in the theatre" , "even more timely" , "more quickly?" , "Theatre worker" , "to give help on the line?" .)