Lady in trouble ahead (4)
I believe the answer is:
leah
'lady' is the definition.
'in trouble ahead' is the wordplay.
'in' indicates the answer is hidden within the clue.
'LEAH' is hidden in the letters of 'trouble ahead'.
(Other definitions for leah that I've seen before include "She married Jacob" , "Jacobs first wife (Gen.29)" , "Rachel's sister" , "Jacob's first wife (Gen. 29)" , "Heal (anag) - girl" .)