Look into playing for money after sunset (8)
I believe the answer is:
gloaming
'after sunset' is the definition.
(literary term for dusk)
'look into playing for money' is the wordplay.
'look' becomes 'lo' ('lo' is an archaic exclamation meaning 'look!').
'into' is an insertion indicator.
'playing for money' becomes 'gaming' (gambling for money).
'lo' going within 'gaming' is 'GLOAMING'.
(Other definitions for gloaming that I've seen before include "half-dark" , "Twilight, dusk" , "not very bright, naturally" .)