Bond performance chasing heart of Octopussy (4)
I believe the answer is:
pact
'bond' is the definition.
(thesaurus)
'performance chasing heart of octopussy' is the wordplay.
'performance' becomes 'act' (act is a kind of performance).
'chasing' means one lot of letters go next to another.
'heart of' says to take the centre.
The centre of 'octopussy' is 'p'.
'act' put after 'p' is 'PACT'.
(Other definitions for pact that I've seen before include "Formal agreement between parties or states" , "Agreement, covenant" , "'Accord, treaty (4)'" , "Treaty, formal agreement" , "Settlement" .)