Boy overwhelmed by a noise in pantomime (7)
I believe the answer is:
aladdin
'pantomime' is the definition.
(I've seen this before)
'boy overwhelmed by a noise' is the wordplay.
'boy' becomes 'lad' (lad is a kind of boy).
'overwhelmed by' means one lot of letters goes inside another (I've seen this in other clues).
'noise' becomes 'din' (din is a kind of noise).
'a'+'din'='adin'
'lad' put into 'adin' is 'ALADDIN'.
'in' is the link.
(Other definitions for aladdin that I've seen before include "Magice lamp finder" , "Pantomime boy with wonderful lamp" , "pantomime role" , "One of the tales of The Arabian Nights" , "Panto lead role" .)