Henry and I save the fish (7)
I believe the answer is:
halibut
'the fish' is the definition.
(halibut is a kind of fish)
'henry and i save' is the wordplay.
'henry' becomes 'hal'.
'and' says to put letters next to each other.
'save' becomes 'but' (I've seen this before).
'hal'+'i'+'but'='HALIBUT'
(Other definitions for halibut that I've seen before include "Marine food fish" , "Something fishy here" , "Large flatfish used as food" , "Fish found in Bali hut" , "Largest flatfish" .)