Work in theatre bound to include good lines (7)

I believe the answer is:

surgery

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'work in theatre' is the definition.
'surgery' can be an answer for 'work' (surgery is a kind of work). I am unsure of the 'in theatre' bit.

'bound to include good lines' is the wordplay.
'bound to' becomes 'sure' (synonyms).
'include' is an insertion indicator.
'good' becomes 'g' (abbreviation).
'lines' becomes 'ry' (abbreviation for railway).
'sure' going around 'g' is 'surge'.
'surge'+'ry'='SURGERY'

Can you help me to learn more?

(Other definitions for surgery that I've seen before include "Medical centre" , "Doctor's (or MP's) place of business" , "consult your MP here" , "Health Service" , "operation" .)

I've seen this clue in The Guardian.

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