Show Dirty Harry is half-hearted (4,5)
I believe the answer is:
blue peter
'show' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'dirty harry is half-hearted' is the wordplay.
I cannot quite see how this works, but
'dirty' could be 'blue' (blue can mean pornographic) and 'blue' is located in the answer.
The remaining letters 'peter' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for blue peter that I've seen before include "Flag flown when about to leave port - TV programme" , "Ready-to-sail flag" , "Flag raised before sailing" , "Flag to show a vessel is ready to sail" , "Flag showing ship is about to leave" .)