One who could have worked with Reed on The House of Usher ? (8)
I believe the answer is:
thatcher
'one who could have worked with reed on the house of usher ?' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'one who could have' is the wordplay.
'one who' becomes 'that'.
'could have' becomes 'cher' (I can't justify this - if you can you should give a lot more credence to this answer).
'that'+'cher'='THATCHER'
Can you help me to learn more?
(Other definitions for thatcher that I've seen before include "Baroness --, former PM" , "man on roof" , "Former prime minister" , "Member of 7 [ORDER OF MERIT]" , "Roof-working prime minister" .)