Dangerously alluring woman again caught in immorality (5)
I believe the answer is:
siren
'dangerously alluring woman' is the definition.
(I've seen this before)
'again caught in immorality' is the wordplay.
'again' becomes 're' (prefix meaning 'again').
'caught in' indicates putting letters inside.
'immorality' becomes 'sin' (sin is a kind of immorality).
're' placed inside 'sin' is 'SIREN'.
(Other definitions for siren that I've seen before include "Temptress - makes a loud noise!" , "She tempts" , "Attractive lady" , "Hooter - dangerous woman?" , "Seductive woman" .)