Next to old king? Good heavens! (2,6)
I believe the answer is:
by george
'good heavens' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'next to old king?' is the wordplay.
'next to' becomes 'by'.
'old king?' becomes 'george' (eg King George VI. I am not sure about the 'old' bit.).
'by'+'george'='BY GEORGE'
Can you help me to learn more?
(Other definitions for by george that I've seen before include "the dragon was killed" , "Animal Farm was -- ----- -?" , "Dated expression of surprise" , "planes might be flown thus?" , "exclamation of astonishment" .)