He originally set up popular current double act: breaking free made him famous (7)
I believe the answer is:
houdini
'breaking free made him famous' is the definition.
(Harry Houdini)
'he originally set up popular current double act' is the wordplay.
'originally' suggests taking the first letters.
'set up' is a reversal indicator.
'popular' becomes 'in'.
'current' becomes 'i' (symbol for electric current).
'double act' becomes 'duo' (I've seen this before).
The initial letter of 'he' is 'h'.
'in'+'i'+'duo'='iniduo'
'iniduo' back-to-front is 'oudini'.
'h'+'oudini'='HOUDINI'
(Other definitions for houdini that I've seen before include "Harry was famous as an escape artist" , "Entertainer bound" , "Showman" , "Escape artist, d. 1926" , "being given to escapism?" .)