Show George, perhaps, helping to end devil (13)
I believe the answer is:
demonstration
'show' is the definition.
(I know that demonstration is a type of show)
'george perhaps helping to end devil' is the wordplay.
'george perhaps' becomes 'monst' (I am not sure about this - if you are sure you should believe this answer much more).
'helping' becomes 'ration' (a ration is a serving or helping).
'to' says to put letters next to each other (I've seen this in other clues).
'end' says to hollow out the word (remove centre letters) (I've seen 'ends' mean this).
'devil' becomes 'deuce' (euphemism for the devil, as in 'what the deuce').
'deuce' with its centre taken out is 'de'.
'monst'+'ration'='monstration'
'monstration' after 'de' is 'DEMONSTRATION'.
Can you help me to learn more?
(Other definitions for demonstration that I've seen before include "Exhibition, protest" , "March; proof" , "Protest march/meeting" , "Display showing how something works" , "Protest meeting" .)